Boost Fr33k

so i just ordered gmpp headers and exhuast. im looking for a good downpipe but im hearing alot about this whistling noise. any suggestions?

question: DP w/cat or w/o, what difference does it make?

Cobalt_SSTuner

iTrader: (1)

go with a cat. I am thinking either XTC or ZZP downpipe. but, I too am interested in this.

Boost Fr33k

dude all im hearing is that the zzp downpipe is producing mad noise... but im looking at intenses and its looks legit for $200.00 but i want some feedback first.

g5mike

Alot of members like their cobalt addiction downpipe

CTCOBALTSSS

Absolutely and I am one of them. No whistles and no leaks. I recommend a CAT as well.

distillion

ive got cobalt addictions, everything fits to the gmmp stuff, its a lil noisy but it sounds good, get lots of compliments, good luck

an0malous

for comparison, my GMPP catback yielded a 15-18hp peak increase on my aeroforce interceptor....
im in no way saying the gauge is accurate on HP.....
but it definately picked up a noticable increase from my catback.

rally

Definetly get a cat

distillion

gmpp cat back is tha ****!
mine stinks though thanks to a plastic bag

Boost Fr33k

good stuff guys, im deff looking into the CA dp.

g5mike

get the 2.5 free flow cat,you can even get the second o2 bung welded in

DWK5150

Im running the Random tech downpipe.

Matty

I had a custom one made. No cat.

g5mike

uuummm, I wonder if you would pass aircare????????

Matty

No need for 7 years. That law just passed a couple of weeks ago.

g5mike

I know.lol the dp I got comming has the freeflow cat,is there much difference????????

Matty

Not much. The catless is only worth a few horses I would guess.

I did it just as much for space, because the postion of the header with the stock cat caused the cat to rub. Deleting the cat freed up space.

c24na

I just finished making my own 3" downpipe too! Made a wicked jig and ya, catless makes for a lot more room!

Have no idea about gains..still haven't driven car. Its still on jack stands

Johnboy12358

The second o2 bung for a wideband has to go before the cat, right? From the pictures I've looked at, it looks like there is not enough room between the cat and the flex part of the CA downpipe for one. then again, I dont really know what I a talking about, yet. Is there enough room to add a second o2 bung in the downpipe there? or should it go somewhere else?

by the way, sorry for the n00bness. I'm learning.

LSJFury

The only DP I see at Cobalt-Addiction is called the "XTC Stainless Steel DownPipe". Is that actually the CA DP and they just call it the "XTC", or is the XTP something different?

Johnboy12358

i think xtc is their brand, but yes that is the downpipe i am speaking of

LSJFury

Thanks.

Second opinions on the CA/XTC DP?

hatrickstu

iTrader: (1)

ill be installing the XTC catless within the next week, so ill submit a review because i am also planning on trying out the spark plug non-fouler trick many other car guys use to prevent CEL's. and BTW, do as much custom mandrel as you can, and look for good deals online, its much much cheaper. so far this is my setup- used GMPP manifold- $160 shipped, XTC catless used- $135, custom 2.5 catback with Dynomax muffler- $185, total investment of $480 for a complete exhaust, patience FTW.

NGalaxyTimmyo

iTrader: (1)

Give Kenny a call, or get into contact with Donna and she'll pass it on. Just tell them that you want a second bung welded in for a A/F gauge. I think it's a little extra, but your gonna have to pay to get it welded in anyways. I went with the catless, so I don't know how much room is left. I'm sure they know what they're doing though.

LSJFury

Does that mean that the XTC DP is one of the ones that throw codes? Even with the Catalytic Converter? I need a DP that has a Cat. Conv. and doesn't throw any codes...