I don't usually post in the General Forum (usually 4th gen. or the SC forum) but since my question spans 2 generations, I'll try here.

As many/most of you know, if you have a '99 to '01 CA emissions Maxima, you can't eliminate your left bank pre-cat when you buy an aftermarket Y-pipe. All '95 to '98 and '99 to '01 Fed. aftermarket Y-pipes eliminate both the left and right bank pre-cats.

Fed:


CA '99-'01:


Well, it has been bothering me lately and I was thinking of gutting my left bank pre-cat on my '99 CA. Has anyone done this? Opinions? I'm guessing it has to be worth at least a few horsepower. I can't think of any major negative ramifications. All other Maximas eliminate their precat with a Y-pipe and it shouldn't affect the smog check since the pre-cats only play a role during warm-up. I actually took down the pre-cat segment last night which goes between the left bank headers and left Y-Pipe leg. The pre-cat is HUGE - about 4" dia. and the 1' segment weighs a ton! Anyway, the question is should I gut the left bank pre-cat? Thanks.

 

how about just taking that exhaust manifold off and cat, and replacing it with a fed spec manifold, and the y pipe elbow piece?

 

Its been done and apparently didn't yield any significant gains:

http://forums.maxima.org/showpost.ph...6&postcount=10

 

Thanks for the link puppetmaster. Good reading...

 

Awesome. Thanks man.