I just purchased a zzp catless downpipe for my 08 turbo. I'm not really interested in doing a catback exhaust. What will I need to connect the 3" dp with the 2.5" gm catback? Probably a simple fix but I am deployed and can't physically look at it, so if you guys can help me out I will have it together that much quicker when I get home.
Thanks

 

Or does it match up as is?

 

It's fairly easy! Did mine in about 45 minutes. No problem bolting up to the stock catback! Here's a how to ......

https://www.cobaltss.net/forums/how-...wnpipe-233857/

 

Thanks, so no adapter needed?

 

Just the knuckle adapter so you can reach the bolt that's on top. That ones a pain in the ass to remove!!

 

Anybody have their car dynoed before removing cat and after? I'd like to know exactly how much hp to expect.

Thank man appreciate the quick answer.

 

No problem man!! You might get about an average of 10-15 WHP from going catless but without a tune, the learn down feature wont allow you to enjoy the added power.

 

GMS1 gets rid of learn down pretty sure.

Raises parameters just like an aftermarket tune.

 

Yes it does! But an aftermarket tune like HP Tuners or Trifecta is better. I had the GMS1 for 2 months then I added a Trifecta tune over that and holy cow!!! It was like night and day.

 

So 10-15 with that?

 

That's about right from what I've read here! I personally did do a before and after when I added my catless downpipe, but I felt it on the butt dyno! LOL

 

Awesome thanks again.

 

No problem man. Stay safe out there!! (read you were deployed)

 

I actually just did these mods on my gms1, didnt notice a big difference mainly just sound i should be tuned before too long so that should change things

 

I'm sure I would prefer a different tune just feel safer with the gms. It operates on similar concepts as the aftermarket tunes so you should have noticed a difference.

 

I'm not sure how they effect fuel mixture and what not, but I know as far as air flow goes gms and aftermarket tunes basically just raise the maximum airflow to a level that could never be reached.

 

nice choice, will bolt up but might get a cel

 

From what I have read it seems like some people do and some don't. I guess I hope I'm just a lucky one.

 

How much of a difference does charge piping make? Already looking for the next purchase haha.

 

Ended up buying mpx catback just didn't seem right leaving stock on there haha.

 

Bought injen charge piping today too. I should probably quit buying things for the day.

 

Nice choices there man!! Just enjoy the money man cuz once you're tied down, you'll always be bitched at! Well I do

 

Haha I am married, but as of right now I make all the money so she doesn't complain. When I get back from deployment different story. Good thing as of today I got all the mods I wanted haha.

 

lol