ok i still have my original main cat has about 200k on it . My question is from what you guys have seen what will my curve look like after adding a test pipe?
I notice many of you running good 1/4 's and high HP #'s dont have them .
Does anyone have #'s from replacing a old cat with a test pipe.

thanks

 

i'm about to do the same, i'm wondering about what gains it gives as well. I'll do it before I go to the track, and if I beat your time, you'll know it does something.

 

Guys... this is exactly what I am getting:

http://www.dmhperformance.com/ecutout.htm

Seems like a good mod so you can keep whatever exhaust (factory or aftermarket) for a nice tone but when you are ready to put some additional power down, just bypass the exhaust. I think this is one of the reasons that 96sleeper is seeing some good numbers.

 

I am in the same boat, thinking about maybe a high flow cat as well. I was also thinking about the cut-out but I don't want to cut up my aftermarket exhaust, any ideas?

 

Unfortunately you might be hard pressed to find dyno numbers specifically for a test pipe. I can't recall anyone dynoing just for that off the top of my head...

If your cat is old and the honeycombs are clogged up you should gain... but how much I'm not sure.

 

thatks i ordered one afew days ago we'll see.

 

a test pipe will not improve or gain any HP unless your Cat is very cloged up. as for the cutout, im on the same boat but with a manual one. on nitrous, turbo, or sc, its best to have the least restrictions possible, with a cutout even better, uber top end..

Im actually looking for a test pipe myself, but without a resonator or anything just a pipe with the flanges, so i can cut it and clamp the cutout to it. found one on ebay for 20something bucks. guy told me its 2.5"