Hey guys,

So, I've got a GMPP Performance catback on my 2.4. It has a good sound, but is a bit droney sometimes. I think the high end drone has to do with the auto not letting it drop as much as a 5 speed would.. I had a ZZP header/dp at one point too, but I didn't like how it sounded with my GMPP, so I'm not back to stock. But I have a few questions..

1) I read in another post something about an SS s/c downpipe. Is the LSJ header/dp any different from my 2.4 one?

2) Should I buy a combo deal from one company for a header/dp or piece something together? Like one companies header, and another ones downpipe. Any specifics to look for then?

3) With the droney aspect, would that really deep drone be from the muffler or the resonator? At some RPM's it sounds mint, but at some it sounds like ass on a stick. Would replacing the muffler and/or resonator help?

Just kinda curious.. Thanks!

 

I can answer part of the first one. The LSJ downpipe is slightly larger in diameter and shorter in length than the LE5 dp. However you have an auto so you'll have to add an extension (I think) or else the cat rests up against the firewall.

Heres a thread that shows the differences between the LE5 dp and the LSJ dp.

https://www.cobaltss.net/forums/2-4l-le5-performance-tech-46/2-4l-auto-dp-vs-lsj-dp-150651/

 

So inotherwords it's not really gonna help me? lol I should just go aftermarket again?

 

Or get a real transmission