kenhebe

I have an 06 ss/sc with GM stage 2, and an AEM cold air intake. Will I be safe if I run a 76mm pulley (GM Stage 3) on my stock exhaust set-up or should I get an exhaust system and then install the smaller pulley? I will be getting a header, downpipe, and cat-back in about 3 weeks, but I do not want to install my pulley now if it is going to cause me any potential harm.

Johnboy12358

the pulley is only 3mm smaller, so I dont *think* it will cause any problems. Its about .11" smaller, so you'll get ~1psi more boost.

kenhebe

Where in the DFW are you. I am in Lewisville/flower mound

Johnboy12358

Denton area
edit: take pictures of your car in the snow the other day?

kenhebe

That would be me. What do yo uthink of the red lights, black grille and blacked out window trim bezel??

Matty

Actually it is only 1.9 MM smaller. 77.9 vs. 76 MM.
1.9 MM = 0.0748".

But you are right about it not causing problems...it might not even cause more boost.

thedubsack85

every herd of a thing called injector duty cycle???

Rage915

here we go again with IDC. LOL

Matty

No, what is that?

Ever hear of a thing called HPTuner?

Rage915

pretty much how much your injectors are being pushed and worked. supposedly your not supposed to go over 88% and running a 2.8 will put it at 90 something, but in my opinion it depends on your location and altitude. i run a 2.8 and my idc is just fine with 42. lbers. plus if you dynotune your car you will be able to see it on your graph and the print outs. this has been a very touch issue, do a search on it read up on it and make your own conclusion from what you read and what you know.

Matty

LOL. I was being sarcastic. I have the same setup but have it HPTuned. I am not worried about my IDC's. 90% is the recommended maximum although some say 80%.

He mentioned IDC's which had nothing whatsoever to do with this particular thread.

Johnboy12358

Looks good

slacker

Funny on my HP tune we leaned injectors out to 11.3 AFR from 10 and are not even pushing the injectors, and will be good for tuning 250 HP did add methonal to end NR because of timing added.

thedubsack85

go ahead and not worry.when you run a 79mm pulley even if u have the stage 2. running a 2.8 pulley will max out your injectors.. i live in cali at 1,400 foot elevation. and if i were to run a 2.8 my IDC would be at 110%.. which isnt good.

Matty

HPTuners smoothes things out. You'd be surprised how the IDC's come down. That being said I would not use a 2.7" on 42.5#er's.