I got started on my exhaust tear down tonight and found something interesting.

We removed everything from behind the cat.

I started the car, sounded MEAN, but didn't seem like it wanted to climb high in the rpms as usual... It didn't rise to 4500 as quick as it did with the complete exhaust.

Any ideas? Am I missing something here?

I hope that it doesn't act this way with a cutout in place of the cat.

 

heh, well i took off my cat back to repair a broken hanger mount, and drove it around for a little while with no cat..

it sounded louder, but behaved almost exactly the same as it did before.... at first i thought it reved quicker in the driveway, but really, i think its my imagination because of the sound...

in anycase, my cars performance is exactly the same... thats not saying much since its only a L03 (for now) but it didnt make much diff.... and it really didnt make it rev slower or anything...

 

it shouldn't make too much of a difference

if I was to see any problem it would only be that the exhuast wasn't long enough to take advantage of the scavenging

but with the y-pipe and everything still there I would think you should still have more then enough room... even with-out the y-pipe you should still be able to have the e ffect of scavenging

might want to try tec-engine see what they have to say