Question on Downpipes
 

whats the difference between a downpipe with a cat converter or without it, and why would i buy one or the other

One with a cat converter has a catalytic converter and will keep you street legal. One without a catalytic converter will run a little better, but is not street legal. Unless you have a programmer, you will have a check engine light and you will fail you state emmissions test if they have them. More importantly, if you get one without and have a warranty issue, they will use that against you.

and one without a cat is a bit louder

if i get the one without it wil give me CEL

yes most likely

than i guess its a no brainer. but how much do you think it does for you having the one without it, and i already have the GM performance exhaust. will i notice a sound difference or performance gain

a d/p without is like 150 i think and one with is around 250 i could be wrong but thats what i think they cost and you will probably gain like 2-4 hp and the sound will be a little different

i heard that fitments suck and you still get a cel with some dp's, true? if not what dp doesnt do that?

I got mine from zzperformance.com and it fit perfectly to my custom 2.5in Magnalfow cat-back system.

It will get raspy

I just put my exhaust on. I have a zzp ecotec header, zzp downpipe no cat and a megan racing cat back. I have no CEL. It is LOUD as hell but i love it

it will get louder, and with some rasp. I have the vibrant exhaust and put a dp with out a cat and made it twice as loud. I plan on getting a resonator to get rid of the rasp

I put on the XTC 2.5" downpipe w/cat after I had on the GMPP sport exhaust, exhaust manifold, and intake, and I noticed a big difference in tone and a bit in power (although I haven't been over 3500RPM yet, only 50mi). I can actually hear my car idling now!! And with all the nasty bends, the stock DP gets down to 2", so I would give the XTC a bit more credit on hp, maybe more like 6-8hp. You have to remember, a high flow cat flows about 95% as a straight pipe the same diameter.

No probs w/ fitment, and no CEL.

i heard the xtc downpipe the flex pipe is like having trouble

only one person has had the flex pipe leak so far, and over 2 dozen have the pipe on this site. I would say that is a fluke.

oo alright i wanted the xtc dp so bad with cat, but then i heard that and didnt want a dp

i was proably going to go with the XTC downpipe. how did it fut up with your GM exhaust

Straight up easy. No pushing or pulling, once the manifold bolts were on, the exhaust bolts just lined up. Absolutely ZERO problems. I have a "How-To" being approved right now, showing the whole process. I'll post a link when its done.

thatd be great

yeah it would be great