an0malous

Ok, so this is all assuming the harrop swap comes out like were all hoping and lives up to expectation.

but considering what we know so far, Id like to have a discussion, and list in this post, what everyone feels would be absolute bare minimum required....and what would be recommended.

almost like the specs on the back of a computer game



so lets hear it. what do you feel, internally or externally, is going to be required or recommended for those of us looking toward this compressor swap.
I admit i have input, but am far from a pro to this, so this is my way of learning, and hopefully providing good information for others to learn too




Required mods:

at least 60lb injectors. possibly larger, and bigger pump may be needed.
Tuning
2.5 inch exhaust system. with good flowing header/dp
intake

Recommended mods:

larger maf (possibly required)
2.75-3 inch exhaust system
Forged pistons
other internals depending on projected rev limit
Secondary HE
Dual pass endplate
Methanol injection
clutch (depending on power, and driver)
axles
mounts.





.

Herndon_High_SS

Required mods
At least 60lb injectors (bigger if the pcm can support it. i heard it can only do 60's any truth to that?)
A good tune

Recommended Mods
a good flowing exhaust system

Witt

Its all going to depend on the size pulley you want to install on it. I'm fairly certain even Harrop doesn't have a real clear idea on how its going to react on our engines.

I can put down a list of what I am doing/did in preparation for it:

Forged internals and supporting modifications to rev to 8k rpm including valve springs and neutral balance shafts.

Higher flowing top end including reground cam shafts.

79lb/hr injectors with a supplemental fuel pump. Reading any logs on turbo cars will tell you where the 60s max at. I prefer not to run the injectors to 100%+. I also prefer a little overhead on the fuel pump's capacity. Engine redline will have an impact on injector duty cycle obviously.

Pretty much all standard bolt ons such as header, exhaust, dual pass manifold, etc.

A retune is pretty much required.

an0malous

hows that look for exhaust recommendations?

what internals would you say fit into each catagory witt?
do you think pistons is pretty much a required?
and the rest recommended?

Herndon_High_SS

I think the pistons will be fine. I would say the rest is recomended.

Witt

Its so hard to say really. Even with a large pulley size this thing "should" move some serious air. You can only go so large before you have to have a custom tensioner pulley fabbed. Recommending engine work and then if this thing flops, would make the disappointment that much worse.

This really falls under the same category as the turbo guys, there are those who run stock internals with a turbo and lay down some serious horsepower but who really knows how long it will last. Most have built their engines before they've nuked so they could turn up the boost. Probably end up being the case here.

I'm thinking of it in terms of a Mopar Stage 3 kit. Works on factory internals but the oppurtunity is there to go crazy if you wish.

It should be recommended to change pistons at the horsepower level the GM build book recommends at least. I guess we will have to see what kind of numbers this thing ends up with.

lsjwannabe

iTrader: (1)

I would recommend running another heat exchanger and dual pass endplate, if your going to run the 2.75" pulley

Pully Police

I agree - The stock Pistons should be fine - as long as the IAT2 temps stay down - which is the entire point of this blower. But basically, you would probably want to look at mildly porting the head, upgrade the valvetrain, 60+lb injectors, dual pass, 2.75 - 3" exhaust, 3" intake, trans mounts, engine mount, clutch, axles, wideband, etc, etc.

TVS_SS

All you need is

• enough fuel for the amount of air (pump + injectors.. because the stock pump will run out)
• Properly calibrated spark timing (you can run more power on stock pistons than you think)
• Ensure your MAF isnt maxed.. if it is.. upgrade and recalibrate

What you want are

• Better flowing heads.. because stock LSJ ports leave alot to be desired
• higher lift cam with proper valve events
• Forged pistons.. everything else should be fine
• Good flowing intake (although this shouldnt be much of a problem)
• Lower pressure drop through the intercooler.. Laminova cores are quite restrictive and dual pass mod only helps Detla T... NOT Delta P!!
• Good full length headers, and low restriction exhaust
• Better drive train (clutch, axles, etc..) because with some slicks.. something will be the weak link

Witt

^^Good post.

As you stated and its been largely left out, the MAF is a big issue. You can only calibrate it up to 11.1k hz if I remember correctly.

an0malous

so maf a recommended mod think?

TVS_SS

Look for any GM V8 MAF.. possibly LS4.. or an LS1 could be a cheaper route plus known calibration values are easy to come by. (granted it will be slightly different depending on your ducting configuration) Connector rewiring may be necessary

Witt

An LS2 "should" be a plug and play deal electrically.

You can also increase the diameter of the intake pipe with the stock MAF to increase it's airflow capability but at the cost of precision.

BlackSS/SC

The connectors on the LS2 and other similar Mafs are different. I had to order a new connector because they are slightly different. GM #15306113

jimbos'ss

iTrader: (2)

here's one that will be pretty much unlimited as far as airflow vs freq:
http://www.lingenfelter.com/store/lp..._lpe-4232.html

Omega_5

I'd say that the intake should be moved to the required section...
I keep thinking of my brothers last Cummins with the upgraded turbo.... he sucked that factory filter in to the turbo one day on heavy load.... don't want that happening to us. Big intake, and a cone filter are a must.

Edit:
Another required mod is -> an owner with a brain.
Guaranteed that some bozo is going to put a sub-3.3" on that bad boy on stock internals and blow the crap out of their car.

TVS_SS

Higher MAF airflow capability sacrifices accuracy at the low airflow range (i.e. idle, cruise, etc..)

All flow meters have a window of operation and you want to size your MAF to be near the upper limits at peak power so that your idle and cruise conditions can still be accurately tuned.

That Lingenfelter unit is for vehicles with significantly more airflow than the R1320 supercharger can provide and you would spend 99% of the time at the very low end of its range

jimbos'ss

iTrader: (2)

so then the slp ls4 maf may be a better choice? it's max flow is 895 cfms

TVS_SS

exactly

shabodah

So LS4 TB and MAF might be a could combination.

2K5SS/SC?

Personal thoughts on minimum requirements to run the 2.75" pulley:
60lb injectors
HPTuners or a tune
Headgasket and headstuds
Full exhaust w/ (min) 2.5" pipe
Intake
Dual Pass Mod/Heat Exchanger
Good Clutch
Wideband to monitor

firestorm

excellent posts, guys.

Coblt ss super

and some head work and have some insane fun

firestorm

is the gm race head an option with this standard block, is it even compatable?

Sharkey

iTrader: (1)

honestly guys, its a blower. you dont need to get all exotic to run the thing.

my list
-header and full exaust
-3" intake
-cobra heat exchanger
-60 lb injectors
-hp tuners

why i say that??? the blower isnt just going to give mopre air, its designed to be a lot more thermally efficient, meaning lots less heat. heat is whats killing our motors. id bet with this blower and a good tuner, 300hp should be pretty easy and safe without swapping rods, pistons, cams, the head, ect.