Help me pick a downpipe with highflow cat and the size. I need one for more air flow and the extra bung for my wideband. Please leave a post and say why after you vote. I will look at this thread for the next week and decide on what to buy.

My current set up: Injen CAI, GMP manifold, GMP Touring Exhaust, GMP Stage II, Ingall's ETD, B&M Short Throw, DC sport Strut Bar.

Future Plans: DP with highflow cat, GMP Dual Pass, C/A H/E, 2.9 inch pulley from Nate, and a dyno tune.

So, with my future plans and current mods what would be the best downpipe. Would the 3inch DP not work correctly with the GMP manifold and GMP exhaust? 2.5" seems like it would be the best for my set up IMO. If anyone can show me why 3" would be better then I'll get it. Thanks alot guys.


Choices I know of.

XTC
ZZP
Rebel

 

ZZP 3" downpipe with a 2.5" exit

 

Already told you, but I say ZZP. I have it, like it. Looks excellent and so far no problems at all. I have the stock manifold, zzp downpipe with cat, no extra bung, and gm perf. exhaust. Sounds excellent together.

I agree

 

Yea, I been stuck on the ZZP for awhile now. It also is the best price and even the flanges are made of stainless. Always good to hear feedback from everyone else.

 

I like the XTC 2.5"

It's a great price and it works well. I have had mine on for a while now.

No leaks, no issues. Good luck man.

Edit: I just noticed the XTC is $249 and the ZZP is $199.99

It used to be the other way around I think. It's been a while. lol

 

Thanks, I can use all the luck I can get. Someone just gave me -rep lol. The comment left: Just buy a DP with highflow already moron!

I just may give the ZZP a try, so much for all GMP. Why does GMP not make a DP with highflow damnit!

EDIT POST: Update, just ordered my ZZP 3" with 2.5" connections so it will fit my GMP exhaust and GMP manifold. Got the extra bung for the AEM wideband so I can install that at the same time. Also got a bung plug for when or if I need to remove the wideband. I'm thinking I'll use the plug and wait for the DP to break in. Then I'll install the sensor. Made sure to order the gaskets, shipped it came out to like 250. Not bad at all. Now, changes since my best 1/4th are: ZZP DP with highflow cat, B&M short throw, GMP manifold, and Drag radials. I hope to pull off a 13 flat! Wish me luck...track times comming within a month or 2!

 

Sounds good Rally. You should be happy with that setup.

I hear you, I don't know why GM didn't make a DP. I guess they didn't want to mess with cats and emissions and what not.