lowpost99

Hey guys, I have a stock intake manifold and a custom CAI. Should I go straight pipe to a muffler now? Don't want to invest in a new cat and don't have to have emissions anymore. Do I need to have computer by-pass or sensor tricks to keep fuel/air trim ok? Can anyone point out where the pre-cat is located? I've read that this was also removed in someone's post

83maxattack

I dont believe removing your cat is going to cause the air-fuel to go outa whack. If what you mean by pre-cat is a second cat (Which i didnt realize they did this in the 80's) then it should be just after the exhaust manifold/header. Or atleast thats what i see on all my newer cars. Although i have no experience with these maximas. My 86' Z didnt have a pre-cat.

lowpost99

You mean a reasonator I think between the muffler and the cat. A11WPower has a build thread where he mentioned removing the pre-cat... maybe I get a photo from him. I did his CAI, and throttle upgrades(stanza) original intake and headers.. just don't want to a freak out between the O2 sensors and computer...any particular pattern I need to ask for? 2.5" in or 3"? I believe 2.5" is stock.

CMax03

iTrader: (3)

No 2" is stock....There are not precats on a 2nd Gen...and it had only 2 O2 sensors if you had precats you would have 4 O2 sensors...You must've fitted 3rd Gen Headers to the 2nd Gen chassis...Been saying for years that it would work....Their very similar in chassis layout and dimensions.

jake0978

I ran 3rd gen headers on a 2nd gen and about to remove them. The down pipe from the header goes right over where the oil filter should be. I relocated my oil filter but the oil pressure is too slow to come up.