Ok, here is a really repetitive post, but nonetheless please help me. I have a GMPP S2, 2.9 pulley and CAI. My final update is the full exhaust (maybe GMPP S3 later). I have ONLY two options. Either full vibrant exhaust, or GMPP manifold and catback. Now i know that u cant really compare both, but I am. I am afraid that the GM parts wont give me much performance, but I am affraid that the 3" is to big (loose to much bottom end, making the car not much faster)! So what would you guys suggest??

 

there is a few threads on this,it seems to be the concencous on here, that unless you are goin for 300 horsies it would serve you best not to go with 3'

 

With your mode level i wouldnt go 3inch, Your going to loose alot of bottom end.

 

Yeah with your mods the 3'' may not be the best thing for you, I would stick with the GMPP, for the mean time. The efficency of the 3'' is way more than your can handle, if you were going for 300 hp or more like ^^^^ he said, then the 3'' would be better for you.

 

Have you looked at the Dezod 2.75" or a 2.5" catback? I looks like you current mods are a little much for the GMPP manifold, so I would stick with the Vibrant 4-2-1 header and DP to keep the mid range power.

 

ok, I'm not trying to hijack the thread or anything, but, say I get the GM Stg 2 which I believe is a 3" pulley, could I just swap to a smaller pulley w/o needing a hub puller or not?

 

Pulley boys make a 2.8 ring for the GM modular hub, but I don't know if anyone else does.

 

It sounds like the best thing for you to do is go with a 2.5" catback system. Theres quite a few systems that run 2.5" I believe also. And if your really wanting to get some HP I'd spend a little more money in a header than the GM Extruded and Honed Manifold. Just my 2 cents though

 

Well my plan was to bring the GMPP manifold to a machine shop and have him open the ports a little if it is possible, so there would be more air being able to comme out. And the reason iam niot getting a 2.5 catback is because downhere (canada) parts are so expensive. The cheapest 2.5 i can find is 800 or so dollars, I can get a GMPP for 400. So half the price. I cant rationalize spending twice the $$ for a few extra hp that the 2.5 would give.

 

$800 for a 2.5" cat-back system!!!!!!!! Wow thats a lot. I would agree with everyone else and go with the GMPP.

 

yeah man, prices are crazy down here. Well the places i called anyways. I mena 5-600 I would be down, but 800+ is WAY to much. Especially when I can get GMPP for 400!!

 

bump

 

I am very curious how u can get the gmpp catback for 400, retail is 538 plus 74 for a tip, and i m not sure why everyone is suprised that a 2.5" is so much the magnaflow system is 679.00 usd on most of the cobalt part sites that doesnt include shipping or install. If u are in canada expect to pay 650 minimun for the GMPP with tip installed getting a bit of a discount, the only way i could see u getting it for 400 is if u worked at the dealer and that still couldnt include a tip.

My research in vancouver

GM Performance retail prices:
Stage 2 kit $965.00+ install
GMPP exhaust: $538+74(tip)+install
Header: 499+install

 

That's in Canadian, in US it would probably be around 6 or 7 hundred something.

Sometimes you have to spend a couple extra dollars for what will suite your application needs best. The 3" with your mods will hurt your bottom end quite a bit, where as the 2.25" should be good for a bit of mods but not open you up for HP quite as well as a 2.5" would. You seem more concerned about money, so...2.25" may be your best bet. Good luck.

 

Well O know Iam getting a good deal, but its 58$ for the tip, so really 458 for the catback and 340 for the manifold!! I am not lying, I can order it tomorrow if I want!!

 

the gmpp exhaust 2.5 and corsa are my favs by far but i gotta change my sport to a touring BOOOO COPS!!!!! but yeah i like these 2 exhausts

 

but GMPP only makes 2.25??

 

can you guys get vibrant 3" exhausts??^^^^^

 

Hello Jim, chek your messages!

 

just save your money man and go to a local muffler shop and have them custom make you a 2.5 exhaust and then just get a gmpp header and a dp

 

Custom shops downhere dont have mendrel bend machines, and their systems are more expensive than a pre-made one(mendrel bend)