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Pre-Cat

Posted: August 1st, 2007, 8:51 pm
by Stoney89
I have a pre catalytic converter on my car right now and i was wondering if there is a way to gut the inside out of it or buy a piece that can go in place of that. I was told that it is robbing me of horsepower, and it is not even neccesary now that the car is not in california. Any Ideas :?:

Posted: August 1st, 2007, 9:55 pm
by bawolvesfan
the amount of power u can gain by gutting your precat is miniscule, like 2 or 3 horsepower at most and the damage you can do to the enviorment is huge, so for the sake of all of us just leave the precat alone

besides opening up the exhaust will move your powerband higher and on the mx3 4 banger that would push peak past redline

Posted: August 2nd, 2007, 8:44 am
by SuperK
the pre cat's main responsibility is to keep emissions low at a cold start.
since the cat is so close to the exhaust manifold, the gasses warm up the cat pretty instantly.
Remember, the cat only does it's job when it's nice and hot.
When your main cat warms up, it'll close to negate the benefit of the precat on emissions, but you'll kill a lot of kittens when your cat's cold.
Still
The best way to remove your pre cat, in my opinion, would be to buy a set of headers. they'll look good and do the job you need it to do.

Posted: August 2nd, 2007, 11:17 am
by Yoda
bawolvesfan wrote:the amount of power u can gain by gutting your precat is miniscule, like 2 or 3 horsepower at most and the damage you can do to the enviorment is huge, so for the sake of all of us just leave the precat alone

besides opening up the exhaust will move your powerband higher and on the mx3 4 banger that would push peak past redline
The main cat would be like 2 or 3 HP. The pre-cat is a straight through flow with the catalyzer material around the outer shell like the packing material in a glass pack muffler so losses are closer to zero and any losses that to occur are because the Pre-cat is too large in diameter creating an expansion chamber to close to the exhaust ports. If anything you will actually be loosing more HP for the OEM exhaust flex-joint than you will from the Pre-cat.

Posted: August 2nd, 2007, 1:49 pm
by Stoney89
bawolvesfan wrote:the amount of power u can gain by gutting your precat is miniscule, like 2 or 3 horsepower at most and the damage you can do to the enviorment is huge, so for the sake of all of us just leave the precat alone

besides opening up the exhaust will move your powerband higher and on the mx3 4 banger that would push peak past redline
Thanxs 4 the opinion but just to let you know livestock, like cows and horses and other big animals hurt our enviornment more than cars by releasing almost twice as much green house gases. So the damage it would do to the enviorment is miniscule. :idea:
Anyway i think i am just going to try and find a header.