BKRBeez

Hey there, first post on here, hopefully it's technical enough for the discussion.

I'm lookin to mod my '08 Cobalt Sport and keep it under warranty so I'm planning on going w/ all GMPP for the job. I was wondering who has had success on here w/ the GMPP parts and what they used and the kind of output increase they gained? I'm planning on having the cold air intake, extruded exhaust mani, and catback exhaust installed. Also, w/ the catback, I've looked all over youtube for good sound clips to compare the Touring package and the Performance package and can't find anything good. Anyone have any video of their vehicles on the dyno w/ those packages installed so I could hear the sound differences and also see the performance payouts?

Thanks for your help!

_UnLiMiTeD_

another thing u may want to add into it is an LSJ downpipe. Still a cobalt downpipe, they wouldnt even notice lol

BKRBeez

where do you find those for sale? looked on google and couldn't find an actual parts site selling official LSJ DPs

Dunkinuts

the 08s have two cats where the LSJ only have one they may notice it.

CobaltCoupeCrazy

iTrader: (1)

I just don't even bother with "GM Parts" for warranty sakes. That manifold isn't worth the money for such little benefit. Intake and exhaust upgrades are always good, however I think the '08's and later all come with the larger exhaust as opposed to my water hose exhaust on the '05; possibly a muffler swap??
Magnusson something or something Magnusson act ?? They have to prove that your after market parts actually cause the issue to deny your warranty. They can be dick about it and give you trouble, but it's a law.

Looking back I realize this is a 2.4L and not a 2.2L. 2.4L should already have the larger exhaust and the larger downpipe. Only the 2.2L came with the smaller exhaust system from block to bumper and only for '05-'07, I think.

BKRBeez

so pretty much if i upgraded to a catback exhaust, it wouldn't yield me anymore power output? would it just change the sound?

Staged07SS

iTrader: (25)

You will still gain power. The stock muffler is very restrictive, and a free flowing muffler/cat-back will free up some hp.

_UnLiMiTeD_

The downpipe on the 2.4's is still smaller then the LSJ downpipe. The 2.2's is like 1.75", the 2.4's is 2.0" and the LSj's is 2.25" or so.

So for the most part, the exhuast on the 2.4 and the lsj 2.0 are the same except for the downpipe and the header

BKRBeez

ok, so i should definitely look at getting an LSJ downpipe, what does LSJ stand for and where can i find one of those? and would it be a pretty noticeable thing to add on, like would the dealership see it there when i bring it in for the other mods?

CordiaDOHC

iTrader: (2)

the LSJ doesnt fit the 2.4 autos from what ive read only the 2.4 manuals.

Staged07SS

iTrader: (25)

the lsj downpipe is 2.75" for the most part. It is only about 2.0" I.D. at the flange that connects to the manifold then opens up to 2.75", and then necks back down to 2.50" right before the flange that connects to the catback. I know this for a fact, because I measured mine when I had it off the car.

BKRBeez

alright, i have a 2.4 manual, sorry i forgot to mention that, so the lsj should fit, even if it's not 2.75 the whole length having it open up some should help w/ the flow and get some extra power out of the exhaust.

now, where can i get one and what exactly does LSJ stand for? was that an engine in the cobalt SS back when it was first released?

Staged07SS

iTrader: (25)

The lsj downpipe (Cobalt SS/SC) will fit a manual SS/NA. 75% of the lsj downpipe is 2.75", so it will deff. free up some power for you. Also, the cat on the lsj downpipe is a high flow unit.

LSJ is the engine code for the Cobalt SS/SC.

Check the site. People always have one up for sale, or are looking for one.

CobaltCoupeCrazy

iTrader: (1)

2.4L and 2.0L LSJ both used the same factory exhaust manifold, downpipe and cat-back.
Also I went from an OE SS downpipe on my car to a Random Technology free flowing cat unit and can feel an increase over the factory SS unit on my 2.2L.

Dave7417

Incorrect. Downpipes are different. Manifold and catback are common though.