Cat change ?

Becustom · January 6th, 2007, 04:06 PM

Would it make any difference if I changed just the cats with some Hi-flo ones ?
I am asking this because I would think that the stock cats would be the most restrictive part of the exhaust system . And by changing them to the Hi-flo cats should make the exhaust sound a little more agressive.
I am asking this because I have always had cars with loud systems but they exited out the rear.
With the side exit system like the corsa is it going to get to loud after a few thousand miles . I have a corsa system on my escalade and it has become very loud over time.
Nyle

**boplaw** · January 7th, 2007, 08:53 AM

I don't think the cats alone will give a significant hp increase. They will help with the cabin heat though. I just bought a set of Random Tech cats to go with my Corsa. My Corsa has 15K on it and is not too loud.

MikeR · January 8th, 2007, 12:52 PM

I had Corsa track wth RT cats. A little more tone then with stock cats. Helped with heat alot. Getting rid of the stock cats is a good thing. But personally I dont think there is much gain on the dyno. Maybe a little.
I did switch out to NO cats and thats where I saw a gain on dyno and alot of midrange, but it is very noisy compared to your setup. For most the power isnt worht the noise,but for me it is.

viper450 · January 10th, 2007, 06:44 PM

I am looking to make my 03 SRT sound better. It is definitely better than the 99' I had before, but still think it should have a bit more throatiness to it. I was thinking of gutting the cats (yes I know, it's not necessarily legal) but thought that may be a way to make it sound better. From your post below it seems as if you have already done this....please confirm and let me know just what type of sound difference it made (what do you consider to be "very noisy"?) I appreciate you time and response.

Quote:

Originally Posted by MikeR

I had Corsa track wth RT cats. A little more tone then with stock cats. Helped with heat alot. Getting rid of the stock cats is a good thing. But personally I dont think there is much gain on the dyno. Maybe a little.
I did switch out to NO cats and thats where I saw a gain on dyno and alot of midrange, but it is very noisy compared to your setup. For most the power isnt worht the noise,but for me it is.