This is for a friend of mine that I work with.. I've tried everything I could think about to try to fix it..
He has a zc in an 90civic SI.. he cant rev past 4500RPM...
The motor seems pretty good besides that.. just some minor valve ticking
I have tried to time it.. timing looks fine.. has new plugs and wires, I tried switching ECU's.. I havent tried a new distributor though? I think that might be it,
but has anyone else ever experienced this? Or know about this? Please help!!!

Very fusterating!!!! thanks