: Catalytic converter and exhaust



Jeremy59
08-04-10, 09:32 PM
Has anyone cut off the cats on a v6? or changed them out for performance cats? I went to the muffler shop today bc i thought i had an exhaust leak and the guy told me that everything was good and when i asked him if i put performance cats on it if it was give it more HP and he said it wouldnt. There was also some kind of object i forget what he called it but its after the cats and both pipes run into it then to the mufflers. He said that if i take it off it would sound better with my exhaust plus maybe give it some more HP bc it would be less restrictive. I am also thinking of putting either 2 1/2 pipes or maybe 3 ' pipes from the cats to mufflers bc stock is 2.25 ..... anyone had any luck ?

CadillacSTS42005
08-04-10, 10:15 PM
the cats are part of the manifolds, dont hack the car up, either contact D3 and get lt headers or forgo cat replacement.
as for exhaust borla and corsa both make systems which can be easily made to work on the v6 car.

Jeremy59
08-04-10, 10:46 PM
ok i figered it out it was the Resonator, has anyone taken it off? so that from the cats to the muffler could be a straight pipe? my car sounds good, but could it sound better without the Resonator?or give it more response? I have asked d3 about headers and they do not have any performance mods for the 3.6 . There isnt even an intake system so i got the intake for the 4.6 and modified it a little.

CadillacSTS42005
08-04-10, 11:16 PM
The Volant intake easily could work on the 3.6 I assume thats what you have, as for the engine its a 3.6, I would assume the Camaro 3.6 DI would be similar to use some of their bolt on parts and since your car is a 3.6 its been hacked for tuning.

Killing the res will get you 5 hp MAYBE a lot of noise but also A LOT of drone which is annoying at best.

Borla is 1100-1500 and replaces the res as its full cat back, Corsa is just can mufflers which sound amazing but will run you 900 for good reason.

Were are you located?

Jeremy59
08-04-10, 11:19 PM
dallas tx, yea i got The Volant intake system, had to mod it to make it fit tho. So the new camero thats out, the engine is the same as my 3.6? Do you know anyone that has got a program for the 3.6 ?

CadillacSTS42005
08-04-10, 11:27 PM
Westers Garage and HP Tuners provide info on that

As for the 3.6 to 3.6 DI I believe they are similar, I know NickCTS had alot done to his 3.6 CTS sport and got it into the 14s which is very respectable.

Jeremy59
08-04-10, 11:39 PM
That helps alot..im deff gunna be giving them a call... dam tho everything for these cars are expensive ... d3 springs 425 and this 495 lol

CadillacSTS42005
08-04-10, 11:57 PM
Asked where you were as I was going to invite you to come hear my STS4 anytime.
As for cost of parts yeah its a Cadillac not a Civic lol, I would probably sell my Corsa for 600 if interested, thats 400 off retail...