I have the GM Performance Stage 1 on my Cobalt with the stock supercharger pulley. I was wondering if the GM Stage 3 computer would work with the stock supercharger pulley (and the fuel injectors from the Stage 1 kit). Would the Stage 3 computer learn to add less fuel to compensate for the stock supercharger pulley? Or, would it always run rich? I want to use the Stage 3 computer only when I am using nitrous and race gas. I heard that the stock supercharger pulley spins the supercharger at the most efficient speed to make decent boost without making too much heat. I really want to avoid the excess heat from the smaller pulley, but I want to enjoy the power from the nitrous tune.

So, if I bought the stage 3 computer and a nitrous kit, would it work with my stock pulley and GM stage 1 injectors? Since I am making less boost with the stock pulley compared to the smaller Stage 3 pulley, can I use a 75 hp shot of nitrous instead of the typical 50 hp shot?

I guess I am thinking outside of the box, but I could really use your help.
Thanks ahead of time
Eric

 

Does this idea seem like it will work? I could use your advice.
Thanks

 

you will def run rich. i suggest doing cooling mods and such before you start putting squeeze in that motor. what kind of set up would you have? i think you should just get a 2.9 pulley, injectors, plugs, and a dyno tune. you will put out same power as you would with the 75 shot. except your motor will be more happy this way rather than the bottled way. your motor will last longer, you will technically be safer. but thats just my advice. i'm sure there will be 30x more comments.

 

No way in ******* hell he'll put the same power with that junk vs spray.

 

SSdan
Do you think my idea would work? The reason that I think it might work is because the tune for the GM Stage 1 injectors is flexible enough to allow you to use the stock pulley, the stage 2 pulley, or even the stage 3 pulley if you have the 2-pass endplate. Why wouldn't the stage 3 computer's tune be flexible enough to allow me to do the same thing? Doesn't the computer adjust how much fuel is being added proportional to the amount of air coming in? If so, I think the stage 3 computer might work with my stage 1 fuel injectors. I need to know more about tuning to know if this would work.

 

once again with the "oh no, nitrous will blow"

Its just like any other mod. if its not installed or tuned right, something will go wrong. If your conservative with it, like a 50 shot occasionally, it will be fine. That size shot is very good for a cooling mod as well as power mod. Your engine will blow with a pulley malfunction, just as much an engine will blow with nitrous. Im not saying a 100-150 shot is totally safe, but the OP asked about a 50 shot.....

i run a 2.9 pulley, meth and a 75 shot along with many other mods.

 

i agree. I don't want this to be an "avoid nitrous" tread. I just want to know if this will work.

 

Honestly, I would skip GM stage 3 all together. Buy a wet kit from a reputable company and be done with it. I have no issues with mine. Run a 65 shot, of course monitor knock, and be done with it.

Also, yes it would work. It's going to run rich since you're not putting in as much air with the stock pulley.

How good it would work, that I don't know.

 

^^^^^^^

Agreed

GM designed the GM S3 kit to run with a smaller pulley(mine is a zzp 2.9). I know mine runs lean when I have the S3 ECU installed compared to the GM S1 ECU claibration that I have installed for the winter(rich as a pig) 18mpg right now with the heat on 2 all the time.

I also have the cooling mods that the S3 calls for though. You run a big risk of running the setup you want to try anf for an extra $1-200 you can have something that you know works correctly

 

Thanks for taking the time to reply to my questions. How is it that the Stage 1 tune can work for the stock pulley, the Stage 2 pulley, and even the stage 3 pulley (when 2 pass endplate is used)? I don't understand how this one tune can work with all 3 pulleys. Can someone explain that for me. I don't know anything about tuning.
Thanks
Eric

 

Gm makes an 'all around all weather any condition' type tune. This is all the GM stage tunes because they don't on power alone. They are reliable and pretty much a fail safe.

 

Pretty much. I won't run the Stage 3 ECU in the winter because it changes the fuel table and runs it lean. Making the motor run hotter hence the dual bypass part that is included in the Stage 3 kit.

The Stage 1 and 2 tune from GM are the same . It's just in the Stage 2 you are paying for a smaller pulley and belt. Kinda a waste of money. I bought my Stage 2 belt from the dealer for $40 and a 3.0 pulley from ZZP at the time for $50. Intstalled myself for $300 cheaper then the dealership.
When I went to Stage 3 I bought a 2.9 pullley thinking that it was a 2.90 pulley that comes with the kit when really it is a 2.99 pulley. I gues I should have stuck with my 3.0 but it doesn't matter that much. Kit still works the same.

The Stage 1/2 tunes are extremely rich because they don't want you blowing up the motor and plus they have to warranty these kits

Stage 3 is not under warranty so they can make the tune the way they want and lean it out because they don't have to support warranty for it

Hope this helps

 

Yes, that helps. Thanks.

 

nitrous will lean the mixture... rich shouldnt be your concern. If you are too rich and shotting wet you can go to a larger fuel pill. lean can cause damage, rich can cause smoke and poor performance

 

Ok. Thanks.

 

First of all running rich with nitrous isnt a bad thing at all....Also the GM STG 3 is designed to work with a dry shot hence if it runs rich the dry shot compensates for that and therefore the car will run leaner and even everything out. IMHO you should buy 60#'s and 2.9" pulley with a dry shot and get a tune for it. That would be the safest way

 

i missed worded my last quote if you are too rich you can go to a smaller fuel pill not bigger. Ive got a .030 nitrous and a .022 fuel and it has given me a very noticable gain, and its not smoking but i dont have a wideband so i dont know if im to lean or not. im just being carefull right now.... and by the way the purge gets alot of girls attention

 

...getting the girls attention with the purge