MRZ Billet Crank Pulleys for the NA ECOTEC's 2.2 and 2.4 are ready! LE5 L61 :twothumbs

We are proud to bring you another high quality performance product for the Ecotec

Link to MRZ Performance Underdrive Crank Pulley - UDP : http://mrzperformance.vstore.ca/product_info.php/cPath/23_24_29/products_id/144

OEM WEIGHT: 1650 Grams OEM DIAMETER: 6.500"

MRZ WEIGHT : 590 Grams MRZ UDP DIAMETER 5.875"

3 X lighter than OEM ! Now that's a radical drop on the rotational mass of your crankshaft meaning your engine will get to revs faster.


http://mrzperformance.vstore.ca/images/custom/pully/ECOTEC/MRZ_UDP_NA_ECOTEC_1.JPG

MRZ billet aluminum UDP versus OEM cast iron pulley:

http://mrzperformance.vstore.ca/images/custom/pully/ECOTEC/MRZ_UDP__vs_OEM.JPG

Link to MRZ Performance OEM size Lightweight Crank Pulley: http://mrzperformance.vstore.ca/product_info.php/cPath/23_24_29/products_id/143

OEM WEIGHT: 1650 Grams

MRZ WEIGHT : 700 Grams

2.5 lighter than OEM !

http://mrzperformance.vstore.ca/images/custom/pully/ECOTEC/MRZ_Lightweight_Pulley_NA_ECOTEC_1.JPG

Satisfaction guaranteed like on all MRZ Performance products!

Just contact me if you have any questions ;) Thanks for looking!

I was just wondering if you guys have dyno'd these to find the results?

Excellent!

When will you be coming out with an alternator pulley to go with it?

I can't buy this right now, but this is definately on my list. :twothumbs

interesting... now do they actually make a difference

I was just wondering if you guys have dyno'd these to find the results?

no now but if someone is interested in testing we can help :guns:

Excellent!

When will you be coming out with an alternator pulley to go with it?

I can't buy this right now, but this is definately on my list. :twothumbs

Alternator pulley are soon to follow ;)

interesting... now do they actually make a difference

They do ;) we'll get dyno # to proove it :guns:

im gonna be supercharged soon i have a 2.4...will this work when im boosted or just for n/a cars only?

im gonna be supercharged soon i have a 2.4...will this work when im boosted or just for n/a cars only?

This is why we have the OEM size pulley, it is the same size as the LSJ pulley but with 5 ribs for those who run superchargers :twothumbs

I would not recommend goind with the samller version if you want to upgrade your powertrain with a SC :guns:

so these are the same size as the OEM pulleys? and i would b interested in doin a dyno.

so whats the deal with the whole harmonic balancer issue? no one has ever been able to provide a solid answer on this.

what will this really do for the 2.2/2.4 motor...quite curious

This is why we have the OEM size pulley, it is the same size as the LSJ pulley but with 5 ribs for those who run superchargers :twothumbs

I would not recommend goind with the samller version if you want to upgrade your powertrain with a SC :guns:

Does the same idea apply for a turboed 2.2?

Alternator pulley are soon to follow ;)
I will buy them when they become a set. How bout AC Compressor pully? If so you have a 100% buy from me.
so whats the deal with the whole harmonic balancer issue? no one has ever been able to provide a solid answer on this.Could you shed more light, what "issue" are you refering to?


Edit, I want the underdrive set: http://mrzperformance.vstore.ca/product_info.php/cPath/23_24_29/products_id/144
What size belt do you recomend with them?

I will buy them when they become a set. How bout AC Compressor pully? If so you have a 100% buy from me.
Could you shed more light, what "issue" are you refering to?

The stock pulley's are harmonically balanced. The rotation of the crankshaft creates vibrations and if the aftermarket pulley isnt balanced the same, then there will be added stress on the engine causing problems later on.

Ahh, true, I understand why he called it an issue but his question threw me off.

Damn those look sexy....

How much of a difference would there be between in power would there be between the stock sized one and the underdrive one? Also how much would the underdrive one affect electrical stuff like lights and stereo and stuff? And finally does the underdrive pulley come with a smaller belt or do you have to get that seperately? No matter what i will be ordering one of these soon just gotta figure out which one.

Excellent!

When will you be coming out with an alternator pulley to go with it?
I can't buy this right now, but this is definately on my list. :twothumbs

Same here
I would want to do both the crank and Alt at the same time I don't really want to take it apart twice.
Tell us when the ALT's are ready will ya

sent u a PM, i am interested in it, id be more than glad to test it out for you, i have a local dyno i go to all the time, they all all my dynos in their system, so i can show before and after's...

i will be testing both the underdrive and the lightweight version of these,
MRZ is sending me both to test out, and you can bet ima let you guys know how each one performs, expect to see pics, vid, and dyno sheets

I still want to know if it affects the electrical components. stereo, lights. etc. Im not putting a sound system in my car, so i wont have to worry about that.

Let us know, do a voltage test, before and after. and let us know if a new belt is needed.

Does the same idea apply for a turboed 2.2?

No... Supercharged must stay as OEm diameter to avoid going smaller to keep the same boost level. You can put the UDP on a turbo and get great gains :twothumbs

Sweet...now I know which one i'll be getting.

I still want to know if it affects the electrical components. stereo, lights. etc. Im not putting a sound system in my car, so i wont have to worry about that.

Let us know, do a voltage test, before and after. and let us know if a new belt is needed.

hmm, i dont have audio, well not alot, i have a kenwood deck with kenwood door speakers, i could run the underdrive for a day or so to see how it affects lights and stereo,

I still want to know if it affects the electrical components. stereo, lights. etc. Im not putting a sound system in my car, so i wont have to worry about that.

Let us know, do a voltage test, before and after. and let us know if a new belt is needed.

If you choose the Lightweight version, there is absolutely no problem eiter if you have big stereo or stock

If you choose the UDP version:

- If you car is stock on the electrical side or have a small sound system installed, there will be no problems with the UDP

- If you have big sound system or other things that takes a lot of power you might experience a power drop...

How much of a difference would there be between in power would there be between the stock sized one and the underdrive one? Dyno on the way Also how much would the underdrive one affect electrical stuff like lights and stereo and stuff? check previous post And finally does the underdrive pulley come with a smaller belt or do you have to get that seperately? Can be sold with or without the belt No matter what i will be ordering one of these soon just gotta figure out which one.
anwsers in bold characters

i changed my sig, fully functional ;) ur side links to ur site, TTr links to TTR

definately will be a purchase once i see proof of their worth. is there anyone willing to do testing on a 2.4?

if we had a 2.4 in our area i woudl talk them into, but all we have r 2.2's and 2.0's...

also after searching i found what the trq spec for the crank pulley bolt is, which is very important to have

first pass= 74lbs-ft/100 n-m
second pass=75*

i would do it if i had access to a dyno. unfortunately right now there is only a dyno or 2 in the city im from but i just moved to a city of 10,000 people which barely has a garbage dump.

so whats the deal with the whole harmonic balancer issue? no one has ever been able to provide a solid answer on this.

Our pulleys are fully CNC machined from a solid billet aluminum bar witch makes them perfectly balanced witch is not the case with the OEM cast iron pulleys that need balancing due to uneven repartition of the material/weight. That said, there is no additional vibrations transmitted to the crank and crank bearing since they are both perfectly balanced.

The vibrations that can be transmitted to the crank are the vibrations from the accessory belt but they are the same on the billet pulley or the OEM pulley since the harmonic on the OEM piece is located inside the pulley itself and not outside like on normal crank pulleys. Take a look at an Ecotec harmonic when it's off the engine and you will see what I'm talking about. That said. Both pulleys contacts the crank and belt directly, so our pulley will transmit the same vibrations as the OEM cast iron pulleys.

I do agree that the best thing will always be to have a true harmonic balancer on an engine with a rubber insulation to cut the belt vibration from the belt. This way of making it is very costly however since 2 parts are needed, vulcanizing, balancing since there are multiple parts assemblem with rubber. This kind of part would sell for a lot more...

i changed my sig, fully functional ;) ur side links to ur site, TTr links to TTR

Nice sig you got there ;)

if we had a 2.4 in our area i woudl talk them into, but all we have r 2.2's and 2.0's...

also after searching i found what the trq spec for the crank pulley bolt is, which is very important to have

first pass= 74lbs-ft/100 n-m
second pass=75*

Yeah, we provide the torque specs with the instructions as well to be sure the install is done correctly

i wud get em..if they were free to test on the 2.4 and go down and dyno them at my friends shop..oh well

Ok, so this is NOT recommended for a supercharger application? What about cooling mods?

Ok, so this is NOT recommended for a supercharger application? What about cooling mods?

the lightweight is perfect for supercharged application :twothumbs

the UDP is NOT recommended for supercharged application :thumbsdow

the lightweight is perfect for supercharged application :twothumbs

the UDP is NOT recommended for supercharged application :thumbsdow

Oh, I didnt read it well enough to realize you had two products for sale in your post. my b.

175 BONES!!!!!! yikes. not anytime soon.

waiting for numbers, then im in

living in montreal, i wanna support MRZ lolol

If we were getting dyno results for you do we get a discount? I have a friend who may allow me to use the his shop's dyno...

If we were getting dyno results for you do we get a discount? I have a friend who may allow me to use the his shop's dyno...

im already on it ;) testing both the underdrive and the lightweight pullies, will provide how-to install with pics, and vid of dyno, and sheets of dyno's

^^^Darn, forgot you were a 2.2

pm sent about 2.4 testing...

^^^Darn, forgot you were a 2.2

:lol: i run SS/Na times if you feel better ;)

Any chance of a group buy?

The crank pulley is not a "harmonic balancer" its a harmonic damper. The ECO engine doesnt require the crankshaft pulley to be weighted and act as a "balancer" since the engine is internally balanced. So reducing the weight of the pulley is fine and should obviously result in freed power.
It does however need a a pulley equipped as a damper to absorb/dissipate crankshaft torsional vibrations. There is nothing we can do about these vibrations other than dissipate them in some way(a damper) or just let them happen and risk the consequences. Everytime a cylinder fires it loads the crank, the crank flexes and then unloads, its this constant loading/unloading that we call torsional vibration. All by itself it doesnt sound bad, but ifwhen this vibration in the crankshaft happens at the same frequency as the cylinder firing event there are now massive forces on the crank that it isnt designed to withstand, the damper absorbs these vibrations so that there are far fewer(ideally no) times when the cranks vibration frequency and the cylinder firing frequency match eliminating the possibilty of these vibrations exerting forces on the crank(and bearings!) it isnt designed to take.

The MRZ pulleys look like excellent pieces, will surely free up some power for you and will most likely offer many miles of trouble free service on your ECO. Just keep in mind youre removing an important design feature that virtually every engine in existance designed for endurance uses.

^^ well then wouldnt getting either aftermarket mounts, or an engine damper thereotically solve the problem once and for all, all the while freeing up more power.

^^ well then wouldnt getting either aftermarket mounts, or an engine damper thereotically solve the problem once and for all, all the while freeing up more power.

No, mounts and engine dampers restrict engine movement, we need a cranksjaft damper to dissipate the vibrations in the crank. Imagine the crank is sitting on the table in front of you, if you strike it with a hammer its gonna vibrate, if there was a crankshaft damper on it the vibrations wouldnt last as long and wouldnt be as severe because they would be transfered harmlessly to the outer mass of the balancer through the damping agent(the damping agent, the rubber or fluid in the damper, is what absorbs these vibrations and simply changes most if it into heat)

hit a tuning fork, it vibrates and sings, do it with your hand on the fork end and all you get is a dull thud and minimal vibrations, your hand absorbed most of the vibrations. Your hand is the damper.



All that said, if my plans for an ECO powered Stlaker come to fruition I would like to use one of these(the Stalker would be a minimal use vehicle)

very interesting, im going to be testing both model on this one, keeping mu stock, i have 35k on my car, with a 72k warranty, so should anything happend im covered, cuz my bud is a tech at the dealer ;) i wonder how long it will be till it causes problems...hmmm...vey very interesting...but still the thought of faster rev'n entrigues me, MRZ i already mad arrangements at my local shop, well nto set in stone appointment, but they now ma go down to yno 3 times, so we came to 150 would cover the 3 runs:twothumbs

sweet, cant wait to see some numbers

MRZ i already mad arrangements at my local shop, well nto set in stone appointment, but they now ma go down to yno 3 times, so we came to 150 would cover the 3 runs:twothumbs
Wow, here it is $50 for 3 runs.

when he said runs, ment runs, he gets 2 pulls

But here it is $50 for 3 pulls or $150 for an hour of tuning/unlimited pulls.

thats nice, i know some places have better deals, but im loyal to this dyno shop, they were the ones that didnt laugh because i wanted to dyno a stock car a while back, no since than i have done all my dyno's with them, i dyno every mod :p

i doubt any big HP gains will occur, but due to faster reving you will reach ur RPMs faster, thus netting you a faster spool, not b/c u spool in lower RPM's, but b/c you get to your spooling RPM's quicker, but i am going to dyno both the lightwheight and UDP, and my bet is i wont say any hp gain, but i will see that the engine will rev faster, think of it as this

set up 1:
2000-6500rpms took u lets say 3 seconds

set up 2(OEM size MRZ)
2000-6500rpms took u lets say 2.6seconds

set up 3(MRZ underdrive)
2000-6500rpms took u lets say 2.4 seconds

in all examples you made the same HP, but its how fast you rev'd that made the diffrence, while i doubt it will add power it will help you make that power faster, thus helping you get down the track faster, hope that helps

i posted that in the 2.4 section, thought i'd post it here too, basically read it, thats what i beleve, i doubt it will add WHP, but i know damn well it will let u MAKE that WHP alot faster...thus helping you get down the track FASTER, now i am still DYNO'n both pullies to see if what/if any HP they make

The underdrive will add a marginal difference in HP but technically it is considered "releasing hp" not "adding".

The underdrive will add a marginal difference in HP but technically it is considered "releasing hp" not "adding".

;).......once more, i am really eager to throw these baby on the rollers...i have set friday up with my dyno shop, that gives MRZ the ability get them to me by thursday, meaning 2-3day shipping

;).......once more, i am really eager to throw these baby on the rollers...i have set friday up with my dyno shop, that gives MRZ the ability get them to me by thursday, meaning 2-3day shipping

good luck! thx for steppin up & testing those for us all!:cool:

i have always been testing thing out for you guys, i tested the OBX header(version1) back when everyone was asking alot of Q's on it, and in a bit more im going to test the OBX header(version 2 that is a shorty with a dp) to see how it fts, works, etc...and this pulley would be something else i would test, i dont mind doin my part for the community

;)
Figured I would bust your balls a little bit. :D

i have always been testing thing out for you guys, i tested the OBX header(version1) back when everyone was asking alot of Q's on it, and in a bit more im going to test the OBX header(version 2 that is a shorty with a dp) to see how it fts, works, etc...and this pulley would be something else i would test, i dont mind doin my part for the community

That's right and my OBX 4-1 header is still on and I have no problems or leaks. I ordered the Leightweight MRZ Pulley (RED) since I have too many aftermarket 12V. accesories to go underdrive.
Anyone else order it?
Less than $200 shipped it's worth it even if I only get 2-3 WHP and quicker revs

it's worth it even if I only get 2-3 WHP and quicker revs

Any power is good power lol

Any power is good power lol

I am looking foward to Jn2's dyno results.
Just picked up a new Crank Pulley Bolt today from the GM Dealer.

so did u order the MRZ or one from GM, or did GM or it for u, i dont get it? and as far as the pulley goes i havent heard from MRZ...they said they would ship it monday when they sent me a PM, still no word from them i have to idea if they are serious or not...what sucks is, if they dont send it i will be stuck dyno'n my car anyway cuz i already paid for the dyno time...i had to in order to be able to get off and change pullies...paid them 150 for 2hrs

so did u order the MRZ or one from GM, or did GM or it for u, i dont get it? and as far as the pulley goes i havent heard from MRZ...they said they would ship it monday when they sent me a PM, still no word from them i have to idea if they are serious or not...what sucks is, if they dont send it i will be stuck dyno'n my car anyway cuz i already paid for the dyno time...i had to in order to be able to get off and change pullies...paid them 150 for 2hrs

I hope they sent them cuz dyno is gonna make it or break it for me for the pulley size and what not...

BTW what mods u got?

my mods r al follows

KnN intake(2.4 SS version)
Vibrant perfromance 4-2-1 header and dp
Greddy EvoII catback exhaust(2.5" stainless steel)
TTR solid tranny mounts
Cosmo short throw shifter

those r them...if i dont get pullies by saturday the latest, i was told i could have my 2hrs friday or saturday, 5-7pm

my mods r al follows

KnN intake(2.4 SS version)
Vibrant perfromance 4-2-1 header and dp
Greddy EvoII catback exhaust(2.5" stainless steel)
TTR solid tranny mounts
Cosmo short throw shifter

those r them...if i dont get pullies by saturday the latest, i was told i could have my 2hrs friday or saturday, 5-7pm

Ok cool you'll be testing with those mods good to know...

Hope u get them by then!

so did u order the MRZ or one from GM, or did GM or it for u, i dont get it? and as far as the pulley goes i havent heard from MRZ...they said they would ship it monday when they sent me a PM, still no word from them i have to idea if they are serious or not...what sucks is, if they dont send it i will be stuck dyno'n my car anyway cuz i already paid for the dyno time...i had to in order to be able to get off and change pullies...paid them 150 for 2hrs

I don't think MRZ is going to leave you hanging after you volunteered to dyno and test fit a new product for them.
BTW I ordered the lightweight version of the 2.2/2.4 Pulley from MRZ. My tracking number shows it left Quebec today. I only bought the 1 Bolt for the crank pulley at the GM dealer since you can only torque it once.

GM Part# 11589123

http://www.crateenginedepot.com/store/images/11589123_large.jpg

I don't think MRZ is going to leave you hanging after you volunteered to dyno and test fit a new product for them.
BTW I ordered the lightweight version of the 2.2/2.4 Pulley from MRZ. My tracking number shows it left Quebec today. I only bought the 1 Bolt for the crank pulley at the GM dealer since you can only torque it once.

GM Part# 11589123

http://www.crateenginedepot.com/store/images/11589123_large.jpg

yup TRQ to yield, trq it to 74lbs, than 75*more i think, well mine is being installed at a dealership by my buddy who work there, so the install will be perfect...and i hope they dont leave me hanging, or else i will be stick with 2 hrs of dyno time, idk what the fuck ima do with 2 hrs of it, i woudl of waited but for dyno time they made me make a appt since i would need it, than need to get off, than get on, than get off, ya know

any news yet bro?

pullies arent here yet, i assume they wont arrive till later next week, as they had to come from canada, also with hurricane ike messing up our weather down here, my dyno money was refunded they said i could just do a walk-in for the dyno, since they have a open book for next week...

from USPS
Status: Foreign International Dispatch

Your item left MONTREAL, CANADA on September 11, 2008. Information, if available, is updated every evening. Please check again later.

im looking froward to the stock lighter pulley test and if a group buy price is right, i got 2 people who want in

Once i see results this is on my list. For Sure

what type of price are we talking if you sold a complete pulley replacement kit.. for the 2.2l

well this one is 200 so the other one will probably be around same price
so 400 bucks im thinking

So were going to need another bolt for when we install these new pulleys?

So were going to need another bolt for when we install these new pulleys?

Yes... its like 6 or 7 bucks for a new center bolt...

Ok. I didn't care how much it cost lol just don't want to be stuck without a bolt. I'm going to buy this pulley once Jn2 gets it dynod and sees a result.

Ok. I didn't care how much it cost lol just don't want to be stuck without a bolt. I'm going to buy this pulley once Jn2 gets it dynod and sees a result.

just dont base your results on the dyno run, i still have doubts that it will add any serious hp, i can see the undedrive adding something, but the OEM one prob wont, the gain is in the faster rev'n not in the hp gained, remember that...:twothumbs

just dont base your results on the dyno run, i still have doubts that it will add any serious hp, i can see the undedrive adding something, but the OEM one prob wont, the gain is in the faster rev'n not in the hp gained, remember that...:twothumbs

plus your gains if any will be significantly different than someone who JUST has the pulley.

plus your gains if any will be significantly different than someone who JUST has the pulley.

i agree every car has different mods done to it so gain(s) are dependent on the mods on the car... also tuning will play a factor...

alright noob question... were does the underdrive pully go? cuz im assumin i should buy both the udp underdrive pully and the light weight pully.

its cool man ask away but yeah the pulleys are the same(meaning they are for the same application) they both are crank pulleys which means u can only have one either underdrive or oem size...

Will these work for an '04 Ion? I haven't heard anyone over on ionforums mention them yet, so I wasn't sure if they'd work or not.

I personally ordered the OEM size neutral color pulley cuz i dont wanna stress my electrical or buy a bigger alternator so yeah plus it fits my build...

Will these work for an '04 Ion? I haven't heard anyone over on ionforums mention them yet, so I wasn't sure if they'd work or not.

I dont see y not... as long as its a L61 ecotec motor...

if the ion has a eco in it than yes it will fit, and u havent heard of them b/c they were just released not long ago by MRZ, they made this thread to let us know

I know this is probably a noob question but where is my crank pulley located in this motor i hear it but i cant see it.

Left side of the motor...
Under the intake and what not...
I'll try to get some pic and post them hold on...

Thanks. I knew it was on the side i just didn't see it. Plus it was getting dark out

Left side of the motor...
Under the intake and what not...
I'll try to get some pic and post them hold on...

UM, I am not exactly sure how you learned to describe engines, or who taught you left and right in relation to engines, BUT the crankshaft pulley is on the passenger(or right) side of the car, basically straight down underneath the MOTOR MOUNT, technically this is the FRONT of the engine.

UM, I am not exactly sure how you learned to describe engines, or who taught you left and right in relation to engines, BUT the crankshaft pulley is on the passenger(or right) side of the car, basically straight down underneath the MOTOR MOUNT, technically this is the FRONT of the engine.

i meant if u looked at it with the hood up under the air intake by the engine mount...
And i'm a mech so i know where and what it is so yeah i work on engines all day long...

i meant if u looked at it with the hood up under the air intake by the engine mount...
And i'm a mech so i know where and what it is so yeah i work on engines all day long...
notice any gains??

hasnt got here yet estimated the 16th

atleast u know when it will be here, USPS has mine, i dont get a estimated day, i just know its on its way here

so Jn2, u are testing BOTH pulleys?

yep im testing both

ok sweet. hopefully the lightwieght one does something.

yeah i cant wait for the results, because I NEED to change my belt really soon.

i will be using a goodyear gatorback belt for the underdrive part # 4050390, and the stock belt for the OEM sized one

i no that we're waitin to c the dyno results but which one would u guys recommend the lightweight oem size or the underdrive pully? and whats the difference between the two?

i no that we're waitin to c the dyno results but which one would u guys recommend the lightweight oem size or the underdrive pully? and whats the difference between the two?

Run OEM size if you don't want to run a shorter belt or if you have a nice audio system setup.

Run Underdrive pulley if you want to have more power.

You will get faster revs with either, just more with an underdrive pulley

well i wana get the best performance so if gettin the underdrive and a smaller belt would b thebest then thats the one ill go wit. what size belt should i use and were can i get it?

If u get the under drive and wanna have a good audio system get a bigger alternator...

I ordered the OEM size cuz i have a system and what not plus i have my doubts about the under size pulley...

i got mine from autozone, part number
duralast ....390k5
goodyear ..4050390

well i dont plan on gettin subs. so ill get the underdrive. and does it matter which belt duralast or goodyear. and those will fit the underdrive rite?

When you mean big system, do you mean something like the Poineer 7 speaker system that comes with some cars and the 10" sub? or mean bigger speakers than OEM and maybe two 12" subs?

i currently have the poineer 7 speaker system.

will more air change anything in electrical power produced? im soon to get the 2.4 intake mani thats why i asked.

i dont want to have the poineer system going and the AC going and loss power somewhere.

thanks

When you mean big system, do you mean something like the Poineer 7 speaker system that comes with some cars and the 10" sub? or mean bigger speakers than OEM and maybe two 12" subs?

i currently have the poineer 7 speaker system.

will more air change anything in electrical power produced? im soon to get the 2.4 intake mani thats why i asked.

i dont want to have the poineer system going and the AC going and loss power somewhere.

thanks

With the 2.4 mani you will be fine dont worry about that but my concern is u running the AC and the Stereo at the same time could stress the electrical in the car and have less power...

If u get the under drive and wanna have a good audio system get a bigger alternator...

I ordered the OEM size cuz i have a system and what not plus i have my doubts about the under size pulley...

I ordered the Lightweight version mostly because I'm concerned about the electric assist power steering on our cars. I don't want any C.E.L. either and that could happen with the underdrive version since your changing the diameter of a crucial engine part affecting the entire electrical system.

I ordered the Lightweight version mostly because I'm concerned about the electric assist power steering on our cars. I don't want any C.E.L. either and that could happen with the underdrive version since your changing the diameter of a crucial engine part affecting the entire electrical system.

thats true but i donno about a CEL part... i guess we'll have to see...

ill post anything out of the ordinary, everything from anything, if it rattles, if it makes a weird sound, if it chakes the engine alot, anything, ill post it all, this is a honest review, hell if the ghost in the trunk leaves my car ill post it too...i know you guys remember the ghost in the trunk

lmao i hate that ghost

ill post anything out of the ordinary, everything from anything, if it rattles, if it makes a weird sound, if it chakes the engine alot, anything, ill post it all, this is a honest review, hell if the ghost in the trunk leaves my car ill post it too...i know you guys remember the ghost in the trunk

Cool
I'll post my review in here as well after I take the car for a test drive.
My Pulley just arrived in the mail today. It will be installed this friday
Yours should have made it through customs by now, Hopefully

Cool
I'll post my review in here as well after I take the car for a test drive.
My Pulley just arrived in the mail today. It will be installed this friday
Yours should have made it through customs by now, Hopefully

customs? what? where is MRZ???

customs? what? where is MRZ???

MRZ is in St. Georges, Quebec City (Canada)
I live on the pacific coast in Vancouver, British Columbia so I got mine fast

i live in texas :( all the way at the bottom of the damn country...i have someone home 24/7 ;) if it arrives, i will be alerted by text message

couple questions guys. Now, I'm 95% sure this is the case, but when using a light weight crank pulley, im gaining whp, but not bhp, correct? it just frees up some hp that was lost in the drivetrain?
and whats the difference between the 2.2 lightweight crank pulley and the 2.0 lightweight crank pulley?

couple questions guys. Now, I'm 95% sure this is the case, but when using a light weight crank pulley, im gaining whp, but not bhp, correct? it just frees up some hp that was lost in the drivetrain?

If you change something on the engine and you get more whp, its because youve got more bhp. The only way to put more power to the wheels but NOT gain Bhp is to reduce drivetrain power loss, that is to make it easier to spin the transmission, final drive and axles/wheels. So switchin to some super efficient lightwieght super lube for your trans would show more hp on a chassis dyno, but you arent actually making anymore hp, a pulley however, if it shows hp gain on a chassis dyno, it will also show gain on an engine dyno. Key point, if it goes in or attaches to the engine to the engine, it can make or lose you horsepower. If it goes in or attaches to the trans it merely USES more or less horsepower

and whats the difference between the 2.2 lightweight crank pulley and the 2.0 lightweight crank pulley?
I am gonna say the 2.2 is a 5 rib belt and the 2.0 is a 6 rib belt

If you change something on the engine and you get more whp, its because youve got more bhp. The only way to put more power to the wheels but NOT gain Bhp is to reduce drivetrain power loss, that is to make it easier to spin the transmission, final drive and axles/wheels. So switchin to some super efficient lightwieght super lube for your trans would show more hp on a chassis dyno, but you arent actually making anymore hp, a pulley however, if it shows hp gain on a chassis dyno, it will also show gain on an engine dyno. Key point, if it goes in or attaches to the engine to the engine, it can make or lose you horsepower. If it goes in or attaches to the trans it merely USES more or less horsepower
a simple yes would have been fine...lol


I am gonna say the 2.2 is a 5 rib belt and the 2.0 is a 6 rib belt

i believe MRZ said that the 2.2 crank was a 6 rib as well...i may be mistaken though. I know its a 5 rib stock, but I believe they were planning on making it a 6 rib for those of us runing after market belts/pulleys...

So how much of an increase in REVs are we talking with an underdrive. I don't feel like spending 200 dollars to gain a thousandth of a second in the 1/4. I mean, do you think a extra tenth or half a tenth extra in the quarter is possible with this.

a simple yes would have been fine...lol



i believe MRZ said that the 2.2 crank was a 6 rib as well...i may be mistaken though. I know its a 5 rib stock, but I believe they were planning on making it a 6 rib for those of us runing after market belts/pulleys...

Well the answer isnt yes, a pulley DOES increase BHP.

If they are both 6 rib I have no idea what the difference could be, I mean shit the number of ribs IS the difference

So how much of an increase in REVs are we talking with an underdrive. I don't feel like spending 200 dollars to gain a thousandth of a second in the 1/4. I mean, do you think a extra tenth or half a tenth extra in the quarter is possible with this.
An underdrive pulley isnt gonna get you a tenth in the 1/4, and it isnt gonna increase your rev limit. What it does is reduce alternator/AC drive speed, if youre spinning the pulleys slower, it requires less power.

Well the answer isnt yes, a pulley DOES increase BHP.



im pretty positive, based on the common knowledge i have and what you were just telling me that a lightweight pulley will NOT make more bhp. The engine will continue making the same power, but less of it will be used to spin the crank pulley, meaning less drivetrain loss (via power lost through the accessory belt).

im pretty positive, based on the common knowledge i have and what you were just telling me that a lightweight pulley will NOT make more bhp. The engine will continue making the same power, but less of it will be used to spin the crank pulley, meaning less drivetrain loss (via power lost through the accessory belt).

Thus "more" power. Less drivetrain loss = more power.

im pretty positive, based on the common knowledge i have and what you were just telling me that a lightweight pulley will NOT make more bhp. The engine will continue making the same power, but less of it will be used to spin the crank pulley, meaning less drivetrain loss (via power lost through the accessory belt).

Your reading too far or not enough into what i wrote, not sure.

Heres how you can tell if you increase BHP or just whp. If the part would show gains on an engine with just the engine(no trans/axles/wheels/brakes/hubs) then you increased BHP, if it wouldnt matter on an engine dyno, its a whp increase. A crank pulley most certainly will alter BHP as measured on an engine dyno.

Maven is rite and it makes sense i donno how else to say it cuz the way he wrote it is perfect but yeah...

Maven props on good write up...

not at all dude....
horsepower is created through combustion chamber pressures pushing on the piston. mods like a smaller SC pulley make the SC force more air into the chamber, thus more, fuel, thus more pressure. adjusting ignition timing can add more pressure. lowering IAT2s can allow you to run more timing and yields denser air for more cylinder pressure. These all create brake horsepower by adjusting conditions inside the cumbustion chamber. Now, Im pretty positive that any mods that DO NOT alter combustion chamber pressures do not make horsepower. Those mods would include: neutral balance shafts, lightweight crank pulley, underdrive pulley, lighter rims, lightweight crankshaft....basically removing any rotating weight. No mod that removes rotating weight will create BHP, however, less horsepower will be lost trying to spin those heavy objects, leaving more of your BHP available to reach the wheels, which is then WHP. So effectively, a 200BHP car that pulls 160WHP, that then gets neutral balance shafts, lightweight underdrive crank pulley, lightweight rims, and a lightweight crankshaft can then be a 200BHP car that has 180WHP, because none of those mods would affect the cylinder pressures.

in your example by the way, the crank pulley is considered part of a drivetrain. its not the drivetrain that powers your wheels, but the drivetrain that powers your alternator, air conditioning, etc

not at all dude....
horsepower is created through combustion chamber pressures pushing on the piston. mods like a smaller SC pulley make the SC force more air into the chamber, thus more, fuel, thus more pressure. adjusting ignition timing can add more pressure. lowering IAT2s can allow you to run more timing and yields denser air for more cylinder pressure. These all create brake horsepower by adjusting conditions inside the cumbustion chamber. Now, Im pretty positive that any mods that DO NOT alter combustion chamber pressures do not make horsepower. Those mods would include: neutral balance shafts, lightweight crank pulley, underdrive pulley, lighter rims, lightweight crankshaft....basically removing any rotating weight. No mod that removes rotating weight will create BHP, however, less horsepower will be lost trying to spin those heavy objects, leaving more of your BHP available to reach the wheels, which is then WHP. So effectively, a 200BHP car that pulls 160WHP, that then gets neutral balance shafts, lightweight underdrive crank pulley, lightweight rims, and a lightweight crankshaft can then be a 200BHP car that has 180WHP, because none of those mods would affect the cylinder pressures.

dont get me wrong ur rite too but if u read what he saying it make sense...

what hes saying makes sense, but i dont think hes taking into account that the crank pulley along with all of the other accessory pullies are adding drag on the system, robbing horsepower. BHP is the same, the above is just stealing some of it, so getting a light weight crank pulley would limit the amount stolen its stolen HP that causes BHP at the crank to become WHP

Well if you wanna get really technical, engine pressure directly correlate to torque production, (IMEP is the engines theoretical peak pressure, this is affected only by mechanical design, BMEP is the engine "brake" pressure or likely average functioning pressure taking into account pumping losses and friction these are key and relate directly to "bolt on" mods) higher effective pressures create more torque, being able to deliver this torque is horsepower, if you reduce engine friction, reciprocatin or rotating mass you alter how quickly the engine can deliver torque.(how quicky torque is delivered is essentially the definition of horsepower ) Lets forget that for now though even though its the key point.

Your getting heavily involved with semantics here, that being "creating" horsepower, versus "freeing" horsepower. This is one issue. The second is you are intermingling the whole bhp and whp deal in their with the "freed" versus "produced" power.

The drivetrain of the car is the transaxle, wheel axle shafts, hubs, rotors, brakes and wheels/tires. All of these things can only REDUCE how much of the power the engine produces is put to the ground. They cant increase it, so if youve got 200bhp there is no way youve got 215whp, we agree on this right?

The engine of the car, as pertains to horsepower ratings given by Chevrolet and every other manufacturer based on the new SAE standards is a fully dressed engine, that is the complete air intake system as found in the car, the airbox, filter everything, the complete exhaust system as found in the car that is manifold cat, muffler, tip, all of it, and ALL accesories and drive systems, that is the serp belt, crank pulley, AC, alternator, power steering, water pump , everything mechanically attached to and driven by engine. Its in this "fully dressed" state that our hp numbers come from , my '08 LS is 148hp based on this test, an SS/TC is 260hp.

When we run my LS on the chassis dyno at Tune time, maybe it pust down 133hp to the wheels, it still makes 148hp at the crank, but only 133 of it makes it to the wheels. Well lets say that we now take my LS and put stupid light wheels, low friction hubs, lightweight axles, smaller brakes and super lube in the trans, and we run it on the TuneTime dyno again....whats gonna happen, well its highly likely that it will now register more power on that dyno, lets 138hp, but if we take the engine and retest it like GM did its STILL gonna make 148hp just like stock, even though my car now puts more to the ground. So did we make more power??? Yes, we made my car have more power to the wheels. Is the engine putting out anymore power??? No. theres just less of it being used up spinning the wheels.


Okay pretend the car is stock again, and weve got 133hp at the wheels, Now lets put on that super light pulley. And we go back to TT, lets say the pulley is awesome and we now get 140hp to the wheels. You say all we did was reduce drag/loss whatever and the car is not really more powerful, well if we take the engine out and retest at GM it will make more than the 148hp it originally did. Why? because we modified the engine and it now puts more power into the drivetrain and more reaches the ground.

I know youre going to say we didnt "create" horsepower, we only freed it by changing the pulley. Well if thats how you wanna look at then I guess its your perogative, but based on that are you gonna then say that exhaust mods dont add power they really just free it? because they dont have the engine MAKE more pressure, they just allow it to breathe more easily and make the pressure it can, same with the intake, the intake doesnt "create" pressure, it just reduces pumping losses and enhances cylinder fill which allow it to make the pressure its designed to...... By your definition only nitrous, blowers, turbos, pistons and combustion chamber size affect power creation, because only these things actually set the maximum potential pressures possibly created.

Ignition timing and mods wouldnt count because they can only adjust pressures within the engines design specs, they cant add pressure beyond what is physically dictated by induction type, and static compression ratio.

Cooling mods wouldnt make power because they dont affect ideal pressure of the engine

Same goes for cams, they cant increase pressure, only tune how much fresh air comes in, how much exhaust goes out and how much static and dynamic compression is allowed to bleed off.

Same for tuning, etc, etc, etc,......very few things actually directly set maximum pressure limits, and anything isnt involved in setting maximum possible pressures doesn "make" horsepower by your definition

Again if its part of the engine it can affect bhp.

yeah not reading all that ill just wait until it gets go my house to see what happens

i read it all...nothin i didnt know, lol its a good read

Well if you wanna get really technical, engine pressure directly correlate to torque production, (IMEP is the engines theoretical peak pressure, this is affected only by mechanical design, BMEP is the engine "brake" pressure or likely average functioning pressure taking into account pumping losses and friction these are key and relate directly to "bolt on" mods) higher effective pressures create more torque, being able to deliver this torque is horsepower, if you reduce engine friction, reciprocatin or rotating mass you alter how quickly the engine can deliver torque.(how quicky torque is delivered is essentially the definition of horsepower ) Lets forget that for now though even though its the key point.

Your getting heavily involved with semantics here, that being "creating" horsepower, versus "freeing" horsepower. This is one issue. The second is you are intermingling the whole bhp and whp deal in their with the "freed" versus "produced" power.

The drivetrain of the car is the transaxle, wheel axle shafts, hubs, rotors, brakes and wheels/tires. All of these things can only REDUCE how much of the power the engine produces is put to the ground. They cant increase it, so if youve got 200bhp there is no way youve got 215whp, we agree on this right?

The engine of the car, as pertains to horsepower ratings given by Chevrolet and every other manufacturer based on the new SAE standards is a fully dressed engine, that is the complete air intake system as found in the car, the airbox, filter everything, the complete exhaust system as found in the car that is manifold cat, muffler, tip, all of it, and ALL accesories and drive systems, that is the serp belt, crank pulley, AC, alternator, power steering, water pump , everything mechanically attached to and driven by engine. Its in this "fully dressed" state that our hp numbers come from , my '08 LS is 148hp based on this test, an SS/TC is 260hp.

When we run my LS on the chassis dyno at Tune time, maybe it pust down 133hp to the wheels, it still makes 148hp at the crank, but only 133 of it makes it to the wheels. Well lets say that we now take my LS and put stupid light wheels, low friction hubs, lightweight axles, smaller brakes and super lube in the trans, and we run it on the TuneTime dyno again....whats gonna happen, well its highly likely that it will now register more power on that dyno, lets 138hp, but if we take the engine and retest it like GM did its STILL gonna make 148hp just like stock, even though my car now puts more to the ground. So did we make more power??? Yes, we made my car have more power to the wheels. Is the engine putting out anymore power??? No. theres just less of it being used up spinning the wheels.


Okay pretend the car is stock again, and weve got 133hp at the wheels, Now lets put on that super light pulley. And we go back to TT, lets say the pulley is awesome and we now get 140hp to the wheels. You say all we did was reduce drag/loss whatever and the car is not really more powerful, well if we take the engine out and retest at GM it will make more than the 148hp it originally did. Why? because we modified the engine and it now puts more power into the drivetrain and more reaches the ground.

I know youre going to say we didnt "create" horsepower, we only freed it by changing the pulley. Well if thats how you wanna look at then I guess its your perogative, but based on that are you gonna then say that exhaust mods dont add power they really just free it? because they dont have the engine MAKE more pressure, they just allow it to breathe more easily and make the pressure it can, same with the intake, the intake doesnt "create" pressure, it just reduces pumping losses and enhances cylinder fill which allow it to make the pressure its designed to...... By your definition only nitrous, blowers, turbos, pistons and combustion chamber size affect power creation, because only these things actually set the maximum potential pressures possibly created.

Ignition timing and mods wouldnt count because they can only adjust pressures within the engines design specs, they cant add pressure beyond what is physically dictated by induction type, and static compression ratio.

Cooling mods wouldnt make power because they dont affect ideal pressure of the engine

Same goes for cams, they cant increase pressure, only tune how much fresh air comes in, how much exhaust goes out and how much static and dynamic compression is allowed to bleed off.

Same for tuning, etc, etc, etc,......very few things actually directly set maximum pressure limits, and anything isnt involved in setting maximum possible pressures doesn "make" horsepower by your definition

Again if its part of the engine it can affect bhp.


heres where your wrong though. your exhaust is not using horsepower...it is limiting horsepower. Getting a bigger exhaust would increase scavenging and flow rates, yielding higher volumetric efficiency, yielding more actual pressure (hp) in the cylinders.

ignition mods also change cylinder pressures, creating horsepower.

cooling mods make a denser charge, and allow more timing, creating more pressure,

cams increase airflow, meaning more pressure in the cylinder.

a underdrive pulley however does NOT create more pressure in the cylinders...

One thing I think you are confused about is when i say cylinder pressure, im not referring to air pressure, like the 14.7 PSIa in each cylinder....i am referring to combustion cylinder pressures, the 100's of PSI that push the pistons down during the power stroke.

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heres where your wrong though. your exhaust is not using horsepower...it is limiting horsepower. Getting a bigger exhaust would increase scavenging and flow rates, yielding higher volumetric efficiency, yielding more actual pressure (hp) in the cylinders.

ignition mods also change cylinder pressures, creating horsepower.

cooling mods make a denser charge, and allow more timing, creating more pressure,

cams increase airflow, meaning more pressure in the cylinder.

a underdrive pulley however does NOT create more pressure in the cylinders...

One thing I think you are confused about is when i say cylinder pressure, im not referring to air pressure, like the 14.7 PSIa in each cylinder....i am referring to combustion cylinder pressures, the 100's of PSI that push the pistons down during the power stroke.

I am not confused though, I am not talking about atmospheric pressure, I am talking about working cylinder pressures. These pressures are dictated by the type(not octane, but type) of fuel being used, the engines theoretical VE, and internal design. There is nothing you can do to an NA engine to increase its power beyond the level dictated by its IMEP(or indicated mean effective pressure) IMEP is the MAX pressure the engine can theoretically create, without losses of any kind. all Exhaust, intake mods, cooling mods, ignition mods, weight reduction mods etc, etc, etc, are just reducing losses in attempt to bring the engines output closer to its IMEP dictated output.

The same goes for a forced induction engine, with the exception that raising boost levels will raise IMEP or potential power, but at any given boost level everything that applies to an NA engine applies to boost, you simply can not make more power than hte engine would if it could operate under ideal conditions, so EVERY mod you make is merely in an attempt to reduce the amount of power lost through imperfect cylinder fill, pumping, friction, power wasted spinning heavy parts, etc.


And to use your words "...is not using horsepower...it is limiting horsepower." Heavy parts, whether it be a pulley, a rod, the crank, pistons, heavy springs are not "using" horsepower, they are limiting it. Hopefully one last example:
Take an LNF, it makes 260bhp. Now bolt on a 10lb crank pulley, a 30lb flywheel, 100lb crank, 5lb rods, 2lb pistons, and much heavier valve springs.

None of those things changed combustion pressures correct?

Will this engine now produce less bhp on an engine dyno?

I am not confused though, I am not talking about atmospheric pressure, I am talking about working cylinder pressures. These pressures are dictated by the type(not octane, but type) of fuel being used, the engines theoretical VE, and internal design. There is nothing you can do to an NA engine to increase its power beyond the level dictated by its IMEP(or indicated mean effective pressure) IMEP is the MAX pressure the engine can theoretically create, without losses of any kind. all Exhaust, intake mods, cooling mods, ignition mods, weight reduction mods etc, etc, etc, are just reducing losses in attempt to bring the engines output closer to its IMEP dictated output.


this is true. however, where a stock exhaust limits the possible power by altering VE/cyl pressures, a pulley along with the other rotating mass has no bearing on the VE/cyl pressures


Take an LNF, it makes 260bhp. Now bolt on a 10lb crank pulley, a 30lb flywheel, 100lb crank, 5lb rods, 2lb pistons, and much heavier valve springs.

None of those things changed combustion pressures correct?

Will this engine now produce less bhp on an engine dyno?

yes...of course it will...but are the cyl pressures decreasing? no..... the same power is produced (not power measured from the engine, but the actual cylinder pressures.

I think this whole debate was me simply using the wrong terms. I guess my original question should have been "will a lightweight pulley stress the engine any more than a stock one?" to which the answer is (im pretty positive) no.

Whats wrong with the MRZ Performance Site?

they something have some problems, it happends to me quite often, they always come back thought

yes...of course it will...but are the cyl pressures decreasing? no..... the same power is produced (not power measured from the engine, but the actual cylinder pressures.

I think this whole debate was me simply using the wrong terms. I guess my original question should have been "will a lightweight pulley stress the engine any more than a stock one?" to which the answer is (im pretty positive) no.

Your revised question is perfectly fine.

obviously a lighter weight part will stress the engine less, you already knew that.

You really want to know if it will make more power, if it will have more horsepower on hte dyno, and the answer to that is yes too.

Where you are using the wrong terms(and its really just more of using terms together that arent directly related) is when you keep stating that since we havent adjusted cylinder pressures with the pulley(which I agree 100% we havent) that we havent created any more power.

Cylinder pressures dont indicate power, they indicate work. Thats is cylinder pressures tells us how much TORQUE an engine can make. Horsepower(power) is how much work the engine can do in a given amount of time. power=work/time

So if we make the engine able to get to a certain speed faster(by installing a lightweight pulley, since we agree this is what the pulley will do) will make it be able to do more work, in less time. By definition, we increased power, even though we didnt change the pressures AT ALL.

Whats wrong with the MRZ Performance Site?

I didn't have any problems with their site....just might have been a glitch on the internet....

I'm game for a group buy :)

<---- Not even a cheap prostitute can match the satisfaction of cheap horsepower :)

If i spend less than 300 bucks and get 10 hp, my pants WILL shrink. I had an issue installing my 2.4 manifold where i couldn't reach inside the engine to install it due to my raging boner.

_______________

On a more serious note, sorry for double post. Would this be one of those upgrades that could REALLY benefit me with a tune? I am trying to just get ONE tune until i go F/I.

I'm game for a group buy :)

<---- Not even a cheap prostitute can match the satisfaction of cheap horsepower :)

If i spend less than 300 bucks and get 10 hp, my pants WILL shrink. I had an issue installing my 2.4 manifold where i couldn't reach inside the engine to install it due to my raging boner.

Weirdo :)

I say with UDP, light alternator pulley, and belt I'd pay about 300 total.

Even 10 to 20 % off of the UDp would but worth it to me.

LOL umrd you like that ? =)

If you had to throw a guestimate out there going w/ the smaller pulley, what kind of power gains do you think are possible? Also I'm still curious as to whether or not its a part that requires / recommends a tune.

You should offer an all black version with no writing, that way you reduce the chance of a dealer tech noticing it.

I had one on my old Neon and I was very happy with it. You could feel the results.

perhaps I will buy then.. soon as i pay down my credit card this bad boy is MINE MINE MINE..
Any ideas on how painful the install will be ? Even tho it probably wont matter those belts scare me lol

Subscribed for Jn2's results

Subscribed for Jn2's results

JN2's results are located in the 2.2L section.

Conclusions, not much change in HP, +- a couple HP but revs much faster than before.

I would really like to see a drag slip from him.

When you say revs much faster. Isn't that faster acceleration?

When you say revs much faster. Isn't that faster acceleration?

Yes because you get to the power band quicker. So acceleration should be much better. Now just get a lighter flywheel and the car will fly through the gears.

I just wonder if we will have to shift more in the quarter mile. Like maybe go into 4th gear

wow weird. I already have to use 4th gear....

Yeah a group buy on these would be amazing...i'd pick one up for sure!

I just wonder if we will have to shift more in the quarter mile. Like maybe go into 4th gear

No, you shouldnt have to shift into 4th if you dont currentyl, without dramatically changing the power output of the engine basically the only things that are gonna affect having to use a higher gears is if you lower the max engine rpm, or change the effecctive gear ratio of the transaxle.

I probably only get to 4th cuz i short shift. I haven't been to the track after putting on the 2.4 intake mani. So my power stopped at like 5800 .. no point in shifting higher than that imho.

its probably faster to run out 3rd gear than to shift to 4th imo. short shift 1-2 and 2-3, but then just they in 3rd till finish

Once you get a 2.4 manifold, short shifting isn't a good idea.

Well umrdyldo like I said I've yet to be at the track since installing the mani. However prior to this just having CAI, decent plugs, & cat back exhaust I was laying down consistent 15.7's.

ill be going to the track this saturday, my last run was 15.79...in the winter, we'll see what i do this weekend

man jn2 we got some close times :) we should line em up sometime :) too bad ur in TX

ill be going to the track this saturday, my last run was 15.79...in the winter, we'll see what i do this weekend

Sorry to ask, I always forget, but what are you new mods compared to the 15.79 you ran?

Good luck at the track, I plan on going in one month from right now.

Sorry to ask, I always forget, but what are you new mods compared to the 15.79 you ran?

Good luck at the track, I plan on going in one month from right now.

thats old mods, i had ebay intake and lsj mani/dp/catback...now i have all my current mods, i havent been back to track yet with these, and im going this saturday, well sunday, well it start saturday night, end sunday morning(midnight madness)

man jn2 we got some close times :) we should line em up sometime :) too bad ur in TX

then maybe you should come down the the lone star bash this spring and race him :beer:

Ya know what. Gimme dates n shit. I got some paid vacation time that I may want to take advantage of.

I actually have yet to make it back to the track since the 2.4 intake mani and header. Prior to buying header I had only gutted out my cat, otherwise totally stock between magnaflow catback and engine.

I'm actually thinking I should be able to pick up a .10th just from adding the ss/sc springs. I'm getting much better front bite.

Jn2 what did u run at the track?

^^^ bunp

i didnt run to great idk whats going on, my best run was 16.1...i need to work on my launching...i launched at 3k and the car boogged down did it for 2k, 2500, and 3k i only got to run 3 times, :( i guess i have launch at a higher RPM cuz the car booged like hell, 60ft was 2.44, ima work on launching than head back, cuz that was rediculous...car has never bogged like that before, it would always pick up after i launched, not drop down to 2k than raise

Could RyanRacer48 have been right? ( referring to another thread on underdrive pulleys ) After all that bashing for just me reitterating what I was told by a professional, I may have been right?

These things are a joke, a lil toy for people who have nothing better to blow their money on.

Jn2, I will agree perhaps the OEM one would be useful for getting the rpms up while the clutch is engaged for faster downshifting.

Could RyanRacer48 have been right? ( referring to another thread on underdrive pulleys ) After all that bashing for just me reitterating what I was told by a professional, I may have been right?

These things are a joke, a lil toy for people who have nothing better to blow their money on.

Jn2, I will agree perhaps the OEM one would be useful for getting the rpms up while the clutch is engaged for faster downshifting.
No, youre still a tool, did you not see that he wasnt launching good?

No, youre still a tool


:lol:

Blunt, haha. :lol:

Haha, yep.

you need to make an underdrive lightweight pulley for alternator that is sized to complement the loss of rotation for the underdrive crank pulley. just a suggestion and i would buy it asap if you had it.

update...idk how many miles i have on it now, but its still kicking good...cant feel it no more as i got used to it, same way u get used to all the other things, hell the tranny mounts ive had more mroe than half a year i dotn even notice :p but yeah still kickin, no signs of trouble, no CEL's pertaining to engine, only 6 from the second o2 not being there...3 codes, 3 of the same active codes pending...weird...but yeah still going strong...i have noticed no drain in the electrical system, im running a optima yellow top if it makes a diffrence

Jn2 nice choice on battery.

And to the guy that called me a tool! LOL Damn u!! :) Your too blunt for my liking!

haha .. Anywho . Just to clarify, I have heard multiple complaints about people having slower take offs w/ this part.

haha .. Anywho . Just to clarify, I have heard multiple complaints about people having slower take offs w/ this part.

Considering this part has been out for about a month and three people have posted about installing it, where do you live/search to hear about multiple complaints about slower take-offs? That makes no sense........Basic common sense says a UDP will simply slow the AC compressor and alternator while the lighter weight takes less effort to spin (BTW overall weight reduction is minimum when you're talking about the engine's spinning mass). Those 2 areas simply free up a LITTLE parasitic power loss.

Referring to underdrive pullies in general. Its a widespread failure. Companies make these to suck up peoples money. I personally have been taught to shy away from these things. I respect and trust the person who told me. I merely was posting my research, if you want it GET IT . I care about my car lasting so i wont be getting it.

i havent seen slower take off, just driver error, i failed to launch at the right RPM, its been a while sincei last went to the track...i dont street race, so i coudnt get enough runs to get used to launching the car...which is what i have to work on now :p i probably wont be going back until later next year when i have more mods

OH ok right on. I knew it jn2 is scared of Ryans Cobalt :)

He wont drive 2 ohio to get smoked ... LoL j/p bro ..

I dig your work and your a class act gentlemen! Keep it up!

i absolutely love this pulley....great job by mrz

Referring to underdrive pullies in general. Its a widespread failure. Companies make these to suck up peoples money. I personally have been taught to shy away from these things. I respect and trust the person who told me. I merely was posting my research, if you want it GET IT . I care about my car lasting so i wont be getting it.

Again you are posting your opinion without backing it up with supporting data. I can respect your opinion if it was based on something substantial. I really don't have a beef with you, but MRZ has gone through the trouble of making a product for Cobalt owners and before it gets fully tested you are stating "something" that someone else said. I prefer to let the facts speak.

As for underdrive pulleys, I guess we need to inform ALL the serious racers of all brands of cars that have them that they don't work and should take them off immediately because they have just been duped into spending their money?!?!?! I guess this would go for the undersized pulleys the 2.0 SC owners are installing on their superchargers....BOY did GM and all the other aftermarket companies fool them. Suprising what a difference little things make isn't it.

No one is saying theUDP pulley will turn your Cobalt into a screaming race car...and for those that want one or are interested let them decide with actual information...provide your in-depth knowledge and I'll even listen.....

Well, I think I've made it pretty clear on here. I'm no mechanic, by any means. I am a IT guy by career that just happens to know how to work on cars. I can't rip apart and engine and put it back together like some of you guys can.

I'm just stating from personal experiences, what I've seen from friends, & finally recently what I was told by the owner of one of CobaltSS.net's top supporting vendors.

My previous car was a 2002 Cavi z24. I had that thing souped to high hell. Prior to the RSM supercharger I had installed on it there was an under drive pulley. I didn't get the OEM size so it was a true under drive pulley. I admit I had a mild system plugged into it, but I ended up frying my entire ECU because something happened w/ my piggy back device being underpowered or something. This failure was the motivation to take it off and supercharge. I had the unit on my car for about 2000 miles, the whole time even w/o the system on, was an obnoxious pain in the butt. I'd be driving and the headlights would at times dim along w/ the dash. I felt NO performance gains from it what so ever. I did see the known increase that it gives in how fast your car revs w/ the clutch engaged or neutral. Unfortunately either due to the pulley itself, or combination of the pulley w/ my piggy back ecu thingy, it would randomly just stall out upon pushing in the clutch while cruising to a stop sign/light. I did have cams on the car, but this problem never happened until the pulley was on.

The gentlemen who explained this part to me a few weeks ago had it on an Impala, and pointed out similar issues. No performance gains, only troublesome issues that didn't have any positives to balance it out.

Don't get me wrong, this is not intended to be a bash contest. I merely am sharing my personal experiences w/ these things and what I've learned recently that further instills my skepticism of this part.

If you wanna risk throwing it on your daily driver and post some dyno results showing it was a worthwhile upgrade, I'll eat my words and apologize for unknowingly providing false information. Until then I feel my opinions are just, and worthy of being discussed.

Your opinion is based on problems you had with your Cavi -- now because of your problems with that car you feel it is necessary to jack this vendor's thread. Frankly, the problems you describe in your post above have very little to do with a UDP pulley.
Fact is this UDP will "slow" the alternator, but not to a point that your car isn't capable of providing electrical power. The alterator can put out FAR more power then the car needs, without a regulator it would be capable of frying every electrical component -- with or without the UDP.

Name the top site supporter who is providing you with your knowledge so we can all get educated.

ive had it on for two weeks...no problems

same here no problems

i wouldn't get the UDP anyway but if they were about $100 cheaper I'd be interested in the OEM size :)

ive had it on for two weeks...no problems

same here no problems

20 days since the install and over 450 Km on my lightweight MRZ pulley and no problems so far.

100 dollars cheaper, this aint no OBX or knock off, this is the name brand, hell even the RKsport udp isnt that cheap

100 dollars cheaper, this aint no OBX or knock off, this is the name brand, hell even the RKsport udp isnt that cheap

lol pullies aren't worth $200+ :lol:

i think it was......

i wouldn't get the UDP anyway but if they were about $100 cheaper I'd be interested in the OEM size :)

Yeah, Id be all over it if it were under $100 too, :lol:

lol pullies aren't worth $200+ :lol:

If they were mass-produced I'd be inclined to agree with you. Parts for our Cobalt are in the initial design and manufacture era. MRZ is taking a chance that they will sell enough to make a profit out of them...time will tell. If they knew they could sell hundreds of them the price would probably be a lot lower.

i think it was......


lets go half on one :cool:

If they were mass-produced I'd be inclined to agree with you. Parts for our Cobalt are in the initial design and manufacture era. MRZ is taking a chance that they will sell enough to make a profit out of them...time will tell. If they knew they could sell hundreds of them the price would probably be a lot lower.

Yeah, Id be all over it if it were under $100 too, :lol:

agree with both, but im hoping for a group buy

Group Buy for the pulleys is now open :cssNET:

And to the guy that called me a tool! LOL Damn u!! :) Your too blunt for my liking!
haha .. Anywho . Just to clarify, I have heard multiple complaints about people having slower take offs w/ this part.
I wasnt joking, dont spread shit if you dont have proof to back it up.
Your opinion is based on problems you had with your Cavi -- now because of your problems with that car you feel it is necessary to jack this vendor's thread. Frankly, the problems you describe in your post above have very little to do with a UDP pulley.
Fact is this UDP will "slow" the alternator, but not to a point that your car isn't capable of providing electrical power. The alterator can put out FAR more power then the car needs, without a regulator it would be capable of frying every electrical component -- with or without the UDP.

Name the top site supporter who is providing you with your knowledge so we can all get educated.
Like I have said in every thread he has posted and been wrong in(quite a few actually) he is a tool. He needs to educate himself on a product instead of listening to someone else who heard from his cousin's mother's sister in law that something is shit.

quick update...still running strong, have not noticed anything out of the ordinary, engine is fine, no CEL(engine related, only have 6 from no rear o2)

quick update...still running strong, have not noticed anything out of the ordinary, engine is fine, no CEL(engine related, only have 6 from no rear o2)

My 2.4L is running fine too with the MRZ UDP...and I don't have any CELs cause I still have my H02S installed:lol:

wut are gains with these pullies?

wut are gains with these pullies?

Jn2 posted a dyno run, HP increase was little, 1-3 HP. Slows your alterantor and AC compressor approximately 10% -- little better gas mileage according to my DIC. Every little bit helps.....