Maven

iTrader: (1)

They are, F23= 3.58*3.84 and F35=3.38*4.05 do the math

I know, but I didnt want anyone else to see the comments and get started on that again.

1niceLS

Ok this is all still well in good but I never said anything about beating LSJs or any of that...Thats all on NWAE all Im asking is for helpful information on a stage 3 cam install or any advice from someone who may have done it thats it. If I wanted to beat an LSJ I woudve gone turbo or supercharged So with that said anybody got any useful information other than don't do it or sell it and buy anoter car?

Maven

iTrader: (1)

Um, youre gonna need your 2.4 TB and a 2.4 manifold, even though you should really get something better manifold wise if you truly want to take advantage of those cams, you should really get port work or consider buying somebodies already built/ported LSJ head, you MUST get valvesprings, you need to get neutral shafts or some variation of a balance shaft delete, you need a nice long tube 4-2-1 header, higher compression pistons would be really nice, not crazy high but 11:1 would make a difference.

PSHHH

where at in maryland you live? id like to see the result of your car if you get it done i might wanna do a N/A build myself depending how it pulls before i work on getting F/I

1niceLS

Cecil County.....right down the road from the drag strip

xxxxsh4d0wxxxx

iTrader: (1)

I wouldn't get 4-2-1.. I'd take 4-1.

NWAE Cobalt

iTrader: (1)

wrong. stage 3 cams are good for higher rpms ...so you want a head that is better up top...aka 4-2-1

xxxxsh4d0wxxxx

iTrader: (1)

^Wrong!

4-1 = Has all 4 primaries merge into the collector at once.. That's better for high end.

4-2-1 (Tri-Y) = Has 4 primaries that merge into 2 larger secondary pipes, and then into 1 collector. 4-2-1.. Get it?.. Better for low end/mid range.

whyyoumadson?

Unless your building for peak dyno numbers you want a 421 header. 4-1 isnt worth the compromise, many of the most advanced NA non-drag engine in the world use multiple merge headers. NASCAR, ALMS, Grand AM, etc......anyone who drives their car at more than one rpm and isnt turbo charged should have a multimerge header.

xxxxsh4d0wxxxx

iTrader: (1)

A properly designed 4-1 header will outperform a 4-2-1.. Here we go again..

Also, we aren't driving ******* drag cars, these are small displacement motors we're talking about here.. You'll never notice the difference, really.

NWAE Cobalt

iTrader: (1)

and if your getting into a stage 3 cam...you ARE talking a drag car

i have a 4-2-1 header on mine, with stg 2 cams and full bolt ons and it DOES give you better numbers.
4-1 is better for all around power, 4-2-1 gets the great scavanging effect going (being longer tube) once you get the exhaust velocity up there (higher rpm)

xxxxsh4d0wxxxx

iTrader: (1)

Dude, lmao, you're getting the 2 confused.. 4-2-1 is good for all around. 4-1 is the scavenging effect up top.

whyyoumadson?

Its nowhere near quite that simple. 421 is pretty much regarded as the best design for NA engines that operate on a wide range of rpm. Like I said, even NASCAR teams who run in circles for hrs on end at basically the same rpm still choose 421 headers because the losses during pitstops, and even mild rpm changes during passing make any benefits that a 4-1 header has at any one rpm mean nothing.

What do we see with a 4-1 header is most people put want long primaries. Thats fine, makes sense right? longer primaries must be good then right? well yeah, but the reason a 4-1 has longer primaries is to try and gain back torque lost by the single merge design. SO 4-1 headers can flow better, but most people end up making the primaries nice and long to try and gain back lost torque anyway.

Primary length and size, collector size shape and number of pipes all determine how things flow, how fast and which way. Basically the idea is to get the gases and the pressure (two seperate things) to travel into the pipes at the proper speed(not too fast OR too slow) to converge with the proper portion of the other gases and pressure waves at the same time and get the most exhaust gas out the tailpipe using the positive pressure waves and gas velocity while using as much of the negative pressure waves created in to the collectors to create as low a pressure as possible in the exhaust port as possible as the intake valve opens to make sure that as much fresh air gets in as possible. And we have to do all this without having the waves collide worthlessly blocking the collector,sending pressure into the wrong pipe, slowing the gases, dropping temperature, reducing efficiency and losing power

Simple, eh?

Buy whatever you like, and deal with the compromises or spend the easily $1,500+ it would cost to get a header truly designed to help your engine.

NWAE Cobalt

iTrader: (1)

this is where clear image auto comes in

and thank you for that explanation

xxxxsh4d0wxxxx

iTrader: (1)

Okay, well the good people over at Clear Image Automotive, who make, arguably, the best header/dp for a cobalt, told me that a PROPERLY DESIGNED 4-1 will out perform a 4-2-1 in nearly every aspect. The point is, EVEN WITH STAGE 3 CAMS, this is a small displacement engine, not a ******* NASCAR.

You tell me why Clear Image is recommending me to buy a header that is cheaper, than convince me into buying the 4-2-1, just because it's more money. If it was better, he would have said so. I'm no engineer, but you can contact them and see what they have to say about your little theory. Hell, give them a call.

They told me that yes, a 4-2-1 will provide a bit better low end/mid range, but it is not worth the high RPMs that you will gain with a 4-1.. I mean ****, you could just get a tune and you'd never know you lost anything.

I don't claim to know everything, but I honestly trust their word more so than yours.

whyyoumadson?

I cant explain why CIA is trying to sell you the less expensive product, honestly the only reason I can think of is that its more profitable, the 421 has more material cost and more labor to build and is only marginally more expensive. ANd yes a properly designed 4-1 header will make more power all over than a mediocre designed 421. Perhaps CIA knows they dont have the proper merge collectors or secondary lengths to extract the highest potential out of the 421 they sell. or perhaps they are simply answering your question about which header they sell will make more power......I cant say for sure since I wasnt involved in your discussion with them and dont know exactly what was said or how it was presented.

As for the NASCAR referrence you are missing the point. Its actually much MORE important on our small displacement small port engine to have a properly designed 421 exhaust to help scavenging and therefore cylinder fill. So if the big 5.8L NASCAR engine(well we could really think of them as a 2.9L 4banger.....) with its relatively huge valves and huge ports still looks to a 421 design to get the best overall power,(as we all should, 4-1 are built for a power peak at one particular rpm) even though they can spend hours at a time over 8500rpm, it would seem silly to believe that our smaller, slower,sensitive engines, that rarely operate over 5500rpm for more than a few seconds at a time, couldnt benefit most from a 421.........

Lets also go back to where I said it really doesnt matter what you buy, theres gonna be very little difference between a relatively short primary 4-1 $207 header and very simple 421 $250 header. Its highly unlikely either one of these headers has any real R&D behind its design, they are built primarily to fit, and be cost effective and easy to produce. How do we know? take a look at the 421 header.......It seems to be the exact same tube set for both, only the 421 has them cut shorter to fit the merge collectors and still be the same overall length.....costs, its all cost. Look no further than the fact that the CIA 421 header used to be a completely different design.

Lets also consider the 421 itself, it doesnt really have and secondary tubes to speak of, just the merge collectors, it used to be a completely different design and CIA claimed it was the only header on the market designed to match the firing order of the ECOTEC, then they changed the order........weird. They claimed it was changed to the "more common" cylinder pairings. Well, I dont know what makes it more common or less but 1342 is the standard 4banger firing order, and whether its left-right numbering like a Honda or right-left numbering like an ECO the cylinder pairs are still the same. Look around for high end tri-y headers , youll see that a vst majority of them utilize the 1-3/2-4 pairing like the CIA header used to, and most of the lesser expensive ones wil luse the easier to build 1-4/2-3 pairing like CIA does now. Coincidence?

Lastly we once again come back to the big issue of cost and other compromises.

Whether you spend $200 or $250 may be a big deal to you, and if that is its understandable ($250 isnt easy to make) but in the real scheme of things isnt a **** in the bucket when it comes to a good header. Ponder this.........a 421 has three merges,if a high quality properly designed merge collector costs well over $100.....how do you sell an optimised 421 header for under $250. Just saying.

xxxxsh4d0wxxxx

iTrader: (1)

Okay, and what if I told you 4-2-1 is better for automatic because your engine rpm cannot reach as high as manual. It will change gear about earlier than manual for most of the gears. Manual is different, you can rev until 9k rpm. When you're at 9k rpm, a lot of exhaust gas will be generated. So, 4-1 is working good here.

whyyoumadson?

Okay, youre set in your mind thats fine. But the fact that on the dyno you will likely never see a significant difference because of the compromises made in headers in this price range, so yu should buy whatever makes you happy. You can tell me all you want about "what-ifs" but Ill just say this, Ive only ever heard of or seen one ECO balt on the street running 9krpm, and it wasnt for very long(seconds) so I highly doubt youre gonna be running that range for any longer.

And as for moving more exhasut gas at 9k rpm yup. But I have no idea why people(you in particular) thik that a 421 flows any less than a 4-1 does. Well I know, its because you dont understand whats going on n the header. Just because a header has multiple merges doesnt mean it flows any less than a single merge header. In fact if ou had paid attention or understood what we want to with a header youd know that its the interaction between the pipes and the gases and waves that determines how well it flows.

A properly designed header isnt a road to show the exhaust which way it has to travel get to its destination. Its a vehicle that actively takes the exhaust there in the best way possible.

xxxxsh4d0wxxxx

iTrader: (1)

No, I'm not set pn anything, I'm trying to figure out which will be better for my build. I just know that the 2.4L intake manifold and the 2.4TB will give you more top end so I figured I would want a header to match, right? Some day down the road I will also be getting cams. Money isn't the object, so don't think I'm going cheap. I don't have the money for a custom made header, no, but I can afford any of CIA's header/dp combo products so I just want what is best for the car. I just can't figure why they'd tell me 4-1 is better.

whyyoumadson?

I am not judging your budget, trust me. Theres a reason my car is still NA I told you my theory on it. They make more money. I could also guess that theres the possiblilty that since the 421 design is such basic design, that it really doesnt offer any benefits over the slightly longer tubed single merge header. Perhaps the 421 design is so much like the 4-1, and so short, that it really doesnt offer the benefits that you would expect from a more heavily engineered one.

NWAE Cobalt

iTrader: (1)

because its probly better for your application. when we say "high rpm" we mean, youve increased your rev limiter and dont want a bottom end
you should see my dyno

and btw, i live 5 min from clear image and have had them work on my car in their shop...and i run a..........4-2-1 header with their dp and exhaust

xxxxsh4d0wxxxx

iTrader: (1)

I will have to talk to them, I want to do my research and buy my part. Not pick some random **** and be pissed with the results. When I quote you and present you with a "what if", I am not saying you're wrong, or trying to **** you off, which I probably did anyway, I'm trying to generate a conversation, you know?.. And generally try to learn from the more knowledgeable people here, ESPECIALLY with this stuff.

They told me that no one buys the 4-2-1.. They said they've sold like 4 total.

Post up your dyno sheet?

NWAE Cobalt

iTrader: (1)

its because:
- you HAVE to buy the combo
- its more expensive
- it doesnt make the power where MOST people make the power at
- they have alot of group buys focusing on the 4-1

for a long time they didnt even make the 4-1, just the 4-2-1

xxxxsh4d0wxxxx

iTrader: (1)

- What do you mean..? Like up top?
- It's $50 more.
- I didn't know you HAD to buy the combo..

NWAE Cobalt

iTrader: (1)

well i suppose you dont, but its going to be easier then having a seperat dp made...cause its a mid-longtube header
the cobalt community is cheap, 50$ is alot to most
and yes. more people street the car and want the power low and some high, as where people looking for the highest numbers/ best racing perf would sac a lil where you wont use it racing for where you will...aka most want it spread out as where fewer want more up top and sac down low.

look at hatrikstu (sp?) - he has the 4-2-1 and is putting down some AWESOME track times
i have the 4-2-1 and am putting down the highest WHP for N/A 2.2
i dont have a current dyno, as the last time i dynod the afr needed fixing and it was pulling ~20whp from me in timing....but..
with cia 4-2-1 header, 2.5" catless cia dp, 3" cia exhaust, cai, mrz alt & crank pullies, 2.4 tb, 2.4 intake mani, a shaved cyl head (.020" taken off), stage 2 cams and a bunch of supporting mods, i put down 180.16whp & 164.91 wtq
once the tuning was finished i carried the power all the way to redline, but i have not been dynod (car is down right now till timed...added 78lb valve springs)