ok today i just got my injectors, injector harness, spark plugs, and a gm belt. and i already have a pully, so i was talking to someone lastnight about it and they said i need hp tuners software, and something with the ecu and to turn off a few senors i didnt order the whole kit because i already have a expensive pulley! who can install all of that i mean i can install everything but the pulley so who would i take it to for the hp tuner software and to shut a few senors off????

 

find a good performance shop with a dyno to tune your car, youve already got the parts you just need your pcm retunned to work with the bigger injectors and more boost, no sensors will be turned off, just the supercharger tourque management

 

Where did you buy the parts from?

When you say kit, do you mean the GM stage kit? What size pulley do you have?

 

ok so how much do you think all that will cost?

i peiced the kit together on www.cobalt-addition.com

and im talking about the stage 2 kit on there but i didnt get that cuz i didnt need all that stuff........ i have a 2.8 pulley

 

a good tune and install at a performance shop could cost you anywhere from 300-600 dollars, i wnet the less inexpensive route and just bought a pcm from intense racing for 200 bucks and had a tech do the install for me, but most would recommend getting a custom tune

 

dam thats alot! you ever heard of balance preformance? or battle ground?

 

yeah, you're defenitley going to need to have a tune man...

HP Tuners will allow you to change fuel consumption and also to adjust duty cycle with the larger injectors. If you were to put all that stuff on your car as is right now, your engine would run like complete ****...your computer is designed to run at a certain injector duty cycle throughout every engine operation from idle to wide open throttle. Example: 20% Injector Duty Cycle on 42 # injectors is going to be more than the 32 # injectors you have stock.

Your computer might just be overly rich by doing this which can cause even more issues for you...the most noticeable is hesitation of throttle, power loss and a check engine light.

I'm assuming you don't know how to tune, take it to a professional. Have them put your vehicle on a dyno and tune it for you. Prices depend on the shop. It would be easier if you found a shop that had HP Tuners so they have credits already but if not, you'll have to buy HP Tuners which is somewhere in the $400-600 amount (i'm not 100%). Shops charge by hour so it might take at most 2 hours if they are a good tuner...if they are more experienced, maybe less. It all depends.

Last but not least, buy a Wideband and a Interceptor Gauge. You'll need it...

 

gotta pay to play

 

If this of course is too much for you...

I'd suggest just selling what you bought and getting a GM Stage 2 kit and calling it a day. Save you alot of hassle.

 

I just bought a 2.85 pulley for our stage 2 and it will be just fine with no custom tune (have 3 friends with exact setup and their dyno pulls were fine with no leaning out and no overly fat pig rich like stage 2 pulley). Stage 2 runs fat pig rich, so when you put a 2.9/2.85 or 2.8 pulley on it brings it right in. Sure a custom tune will run better, but its not absolutely necesarry (but 2.8 is the point it will need a tune depending on other mods like exhaust and intake etc..). I just bought hptuners and it was $499. Ill be using it on my Z06, the Cobalt and a few friends cars. Like mentioned about get a nice wideband gauge for around $300, and keep an eye on it.

 

Its not that it runs real lean its that it over works the injectors. I ran a 2.8 on the stage 2 and my idc was 118% at 6900 rpm's. But alot of people are running that setup with no injector problems.

 

Yeah, that's no good. Injectors going static = bad!