ok i have a 07 cobalt ss/sc it has approx 40000 miles on it and i wanted to put a stage three on it but i wondering if i could go down to a 2.7 pulley with out having any troubles i know i have to have a dp he and others just wondering if it would effect anything else any advice would help thank you

 

It will be to much boost for the s3 timing...ppl have done it but u would need like every cooling mod..

I know some one selling a s3 pcm for 06-07 ss sc

 

You can get the zzp s3 kit with the 2.7 its an option

 

Run water/meth and you'll be fine.

 

Yea without E85 or Meth you'r going to get reduced timing into top of third and up.
Go 2.8 or 2.9.

If you have Dual Pass and Phenolic Spacer you could probably run a 2.7.

Whatever you do any companies canned tune will hardly gain you any real power.

 

I wouldn't run a 2.7 on stage 3, the S3 tune is leaner than S2 is. Running more boost would be a recipe for disaster. Also the S3 tune is not designed to work with Meth so I would avoid that as well. Cooling mods are a good idea though. Phenolic, dual pass, griffin HE, and ported blower would all be fine.

2.99 is as low as you should pulley on GMS3. Running a 50 shot of nitrous is perfectly fine as well it's designed for that.

 

thank you for the advice so it looks like ill be getting a 2.8 what was your hp and tq for a 2.8

 

I wouldn't run anything smaller than a 2.99, you are really asking for trouble. These other guys don't know wtf they are talking about.

 

I second this..
The amount of kr u will have will destroy ur engine

To much boost for the s3 tune..
If u want to run more boost get zzp s3 with a 2.7 and 50# injectors and drive the hell out of it..

 

I just purchased a 2006 ss sc that has 60 lb injectors and a 2.7 pulley on it . It has the the stage three kit . And runs coolant temps between 180-200 . It has a 2.5 inch magna flow cat back and zzp down pipe . It runs about 18 psi of boost . It runs great . I have contacted a macanic And friend. I think everything else is stock . As far as the cams and other recommended internal parts. What should I do if that's the case ? Down size pulley and retune?

 

I meant upsize not down size.

 

Engine coolant temps dont show how hot the air going into the engine is u need to get an aeroforce interceptor to watch ur intake air temps, u will have a iat and an iat2 u want to make sure the iat2 dont go over 140 while going redline, u also need to have cooling mods for a 2.7 pulley do u have any cooling mods? Also check ur ic pump make sure its not dead. Get ur tunes checked also by a good tuner to ensure its a good tune. U will need alot of cooling mods to not over heat the air coming into ur motor with a 2.7 pulley. Also with the interceptor that is a knock retard 1 2 and 3 go to 3 and make sure ur not getting knock when going redline. If u do u need to have it checkes by a tuner cause knock can kill ur engine

 

The smaller the higher the boost, but if u go to small without cooling mods to keep the air cool u will loss power by heat soaking.

 

I don't have knocking I also have a dp / he the pump is good and tomorrow i am taking it to a professional tuner and I think i am going to get a larger pulley because i don't intent to race it all the time . Haha no need for the 2.7 but thank you for your help!

 

Oh no! My 2.8 pulley is going to blow my car up????? AHHHHHHH!!!! Ur telling me that zzp was wrong and that they lied to me and my car will DIE?????

 

You can run a 2.7 just as long as your cooling mods are up. It won't hurt

 

He was talking about GM stage 3 not ZZP stage 3, zzp stage 3 tune will be set according to what options u selected when u bought the kit.

 

Id just go to a 2.8 if u dont want to run the 2.7, if u have dual pass and H/E upgrade then u should be good but id add the opt b into that mix to insure that u bleed ur system real good for max cooling. May also consider a phenolic spacer from zzp also if u do decide to stay 2.7

 

Yep, info above sounds correct, I would at least go 2.8, trust me, you'll get there eventually

 

I'm running 2.7 on trifecta GM stage 3 but Vince changed the tune for my mods . Car has ran great other then I think my bpv is bad.

 

If the tuned was changed then its no longer a gm stage 3 tune.

 

Its a stage 3 tune. He had to make changes do to the fact I have bigger injectors then the 42 lb also smaller pulley its still GM stage 3 because I still have HOM AND ADJUSTABLE REV LIMITER

 

That would make it a custom tune with hom and adjust rev limit, if u was totry and sell it too someone looking for a gm stg 3 tune it wouldnt work with their gm stg 2 injectors, changing the injectors used for a tune is a pretty big change to the tune its not like lowerig boost in first gear for traction or anything small like that.

 

Its still stage 3

 

U can call it what u want, u can call a horse a cow or a dog a cat, just saying it dont work with gm stg 2 components anymore.