Originally Posted by Bad06SS

I'm just messin with you, no "oozing sarcasm". But in all honesty, there's no proof that you actually lose torque by getting rid of the cat. If I had the money, I would dyno the car with a cat, and then without to prove it's worth more than 1-2 horsepower. Also, Dan, if I recall, you were only trapping 103ish when you raced with Rob, and were getting KR. Funny how when you finally took the cat off, you trapped closer to 109 and didn't have kr?

Originally Posted by djt81185

I had 1 106 trap wth the cat...then that crappy night at muncie i ran like 104 ish all night i think...then i had cat removed and went 107+ consistantly..We had 2 car setup identical here and the one w/o the cat (mine) would always pull from 40 on...its definately worth the power and KR reduction

Originally Posted by djt81185

I had 1 106 trap wth the cat...then that crappy night at muncie i ran like 104 ish all night i think...then i had cat removed and went 107+ consistantly..We had 2 car setup identical here and the one w/o the cat (mine) would always pull from 40 on...its definately worth the power and KR reduction

Originally Posted by djt81185

Btw..new trans got approved today ill have it back bfore i come back to school

Originally Posted by SS33

Ok, I'm sold now. I was already leaning towards this route anyways,,, I was having major heartburn at the thought of spending the extra cash for a high flow cat.

I love Michigan for not having sniffer tests. We don't need no stinking cat

Now the only question left is, at what boost levels would the 3" show benfit as compared to the 2.5"??

I'll probably never go further than my 2.8" pulley,,, maybe a 2.7 eventually, but not in the foreseeable future.

Is there any reason that I should NOT go with a 2.5" DP?

Originally Posted by bluecobaltss06

OK guys, I read a great article on this in a performance catalog. The did a dyno test with a straight pipe, and magnaflows high flow cat. They only showed a 1-2 hp difference with the test pipe. Now you have to realize by not having a CAT you are breaking a federal law. So is it really worth the 1-2 hp?

Originally Posted by Jackalope

So how do you get it to not throw a CEL with no cat?

Originally Posted by SS33

HPTuners FTW

I think I will go with the 2.5" catless. That should be good for all I'll ever wanna do with her.

Now just hafta make up my damn mind on a header.

With my luck though I'll buy the DP, and a week later someone will announce a full long tube header,

Originally Posted by SS33

HPTuners FTW
With my luck though I'll buy the DP, and a week later someone will announce a full long tube header,

Originally Posted by CTCOBALTSSS

XTC downpipe and header, total $370.00 plus $50.00 shipping = $420.00

Can't beat that my friend. Good quality stuff too.

Originally Posted by Bad06SS

CTI is the most long-tube out of the current header's made, I decided to go with their header and a catless downpipe.

Originally Posted by SS33

I agree,,, and I may go that route. But if I get a 3" header,,and 3" DP,, I know I'll talk myself into a 3" cat back,,, and I just don't know if I need, or want to go full 3"


decisions, decisions, lol

Originally Posted by Bad06SS

Off topic: I had mine custom made to bolt up to my Corsa. I see no reason to get rid of my Corsa, it flows just fine and sounds great! So it's a CTI long-tube, with a 3" collector, 3" downpipe, flanged to bolt up to my Corsa.

Originally Posted by SS33

Did CTI, do that flange for you? Or did you have it done locally?

Originally Posted by SS33

Came very close to buying that exact set-up until I noticed the 2.25" collector

Not sure I dig that very much. Now I'm back to being undecided.

Originally Posted by Bad06SS

Sorry, I don't agree. I would say there's a good 10whp going to a straight pipe. The stock cats are restrictive, and on top of that, they get too hot and fail alot because they can't keep up with increased boost. I've personally looked at our stock cat, and you can't even see through to the other side! Putting a straight pipe in decreases kr and boost, and I've seen nothing but benefits from mine. Also, unless I see proof, I'm calling BS on the loss of low end torque as well. With that said, you're exhaust will become alot louder, and sound more raspy, so choose you cat-back wisely. I happen to think that the Corsa Touring sounds great with no cat!

Originally Posted by bluecobaltss06

OK guys, I read a great article on this in a performance catalog. The did a dyno test with a straight pipe, and magnaflows high flow cat. They only showed a 1-2 hp difference with the test pipe. Now you have to realize by not having a CAT you are breaking a federal law. So is it really worth the 1-2 hp?

Originally Posted by Smokem10

is the high flow CAT worth the money?