Originally Posted by Irving216
which year has a smaller one and how much smaller was it?
The 92-93 Gen 2 m62 has a 2.5" pulley
Your 94-95 Gen 3 m62 has a 2.8" pulley
I would scan the car for KR at WOT before you drop the pulley size. You could be seeing KR already, stock.
Also, those tubular exhaust manifolds flow well but tend to crack at the welds often causing false KR. You should remove/inspect/repair them.
Your downpipe is single walled and larger than a stock Series 2 DP. The cat is the bigget restriction in the exhaust.
Originally Posted by Mike1995
Considering he'* a 95, he is already half way there to a full OBD2 system. Grab an L67 engine and PCM from a 97. Modding possibilities are almost endless.
There'* no real need to go OBD2 with a 94/95. All you need is a 95 L36 engine harness and a custom tune from gmtuners.com. Even though nobody seems to want to do it, these pcms are very tuneable.