I was wondering if i got just the front manifold ported if i would notice a difference or do i need to do both. Because i have an extra front just kicking around and i have a 95 so i would have to take them off and send pector mine to do and if i could do the front only right now and get a little gain then i would do that for now. Give me some input guys thanx.

I guess the front manifold is the worst of the two. Getting just the front ported should get you somewhat of a gain. However, the rears don't flow all that great either, so if you ever get the chance, I'd say get both done.

yea i am going to. I think i am going to talk to peck and have him do my front up. Then maybe later this summer send my rear to him. thanx
ps. The front one on our cars are all the same correct because that one is from a 2001 gp.

I've got a grand prix front and it was the same as my 95. The rear off a 95 though is very unique though. It has a pipe looking sleeve that comes out of the rear hole and goes into the downpipe. no other L36 manifold has that that i'm aware of. I do have a 95 rear manifold just sitting in my garage that I can't use anymore. If you want it for a spare, i'll sell it $20 plus shipping. BUT that sleeve i was talking about is bent from when i tried to take it out. I can take pics of it and you could send them to pector to see if he can replace it. but you need that piece and probably only that manifold or it will not attach to your downpipe correctly.
That sleeve has a wire mesh gasket(unlike other L36 years) that goes around the sleeve, which holds it in place and it also slips into the downpipe.

i dunno. I would rather not play around with anything that i need to fix lol. I am probably just going to do the front for right now. But if you would post a few pics i would like to see what you are talking about though.

For me the front was a great KR killer, i went from seeing up to 8* of KR to 2-3 at WOT.

There were 14 different exhaust manifold part numbers from 92-99, so be careful when selecting your cores for porting.

oh i dunno then i might just wait then.