I'm running a LQ4 all stock with a LS6 cam and masterpower T76 turbo. I recently switched to an ISKY 218 cam and GT45 80mm turbo. My car ran great before the switch and now it won't even idle. I know a lot of the truck guys run this cam.

Does anybody using HP Tuners have a basic setup to get me going? I'm reading thru various post about tuning for large cams and all but this cam isn't considered very large is it? Also will I have to redo my entire tune to pick up where I left off or just correct the idle portion? Any help will be greatly appreciated.

 

I agree that isn't big enough to not idle at all. Sounds like a vacuum leak, did you pull the intake or throttle body?

 

No I didn't pull any of that. I was able to get it running using an idle tuning guide from LS1 tech. I'm gonna keep working on it to try and get it a little smoother.

 

Post your tune so the experts can look. Sound like a vacuum leak or something else. I put that cam in my 5.3 replacing the stock cam and it idled fine and drove fine before it was tuned.