Hey everyone, so I have a question about the 91 Z28 I just bought (350 TPI auto). The guy who owned the car before me had put an aftermarket cam in it and it was idling shitty since the ECM wasnt updated for the new cam so I was looking to have the correct chip burned for the new cam but I found out that this guy lost the cam specs so I'm gonna guess that unless I pull the cam and degree it, I pretty much have to deal with the shitty idle, correct? Thanks, and I hope I didn't ramble too badly.
~Colin

 

You need to either find someone local to you who can burn chips, or buy the equipment to burn chips yourself. You dont need to know the exact specs of your camshaft, as most larger cams will make the 90-92 system run rich at idle. Lean it out and it'll idle better. For a temporary fix, see if raising your initial timing from 6 degrees to 10 degrees helps any. You can also try opening the throttle blades to make the idle higher, but that is a band-aid fix.

 

So if I find someone to burn me a chip, how will they be able to burn the right chip for my car without the cam specs? Also, maybe anyone with any experience with someone in the eastern PA region would help too. (I dont mean to sound too newb-ish but the TPI system is new to me. . .my other car was a carb'd 86). I'm not sure if this would work but the 86 has a bigger cam (that I know the specs of) and I was wondering if I could just switch the cam and get a new chip burned to match it? Would this work? Thanks for the help.
~Colin

 

It would be a trial and error situation with experience thrown in.