Celica Forums General Discussion Exterior anyone know how to take off the catalytic convertor?

yea, i was just wondering if anyone knew how to take off the cats to gain some extra hp. i hear it's like a 20 hp gain. oh yea, does anyone know how to also make sure that the check engine signal doesn't come up? because i'm sure that'll come back. what kind of straight pipe should i use to? where can i get one, or am i going to have to custom fabricate it? i'm bringing my car over to europe so i'm not going to need to get the car inspected anymore, so might as well take de-cat it and run some leaded fuel, lol.

ok removing the cats 4 bolts that come off easy right? now you got a section of piping thats open thats basically running off the header. what to do then is to take it to a muffler shop and ask them for a test pipe they will make a mid pipe with flanges so that you can remove the cat and swap it with the test pipe. as far as check engine lights go not sure.

Also this will not gain any hp. itll just sound a little more high pitched and the only differance youll notice is at high revs itll respond just a little better. again no real hp gains just a very small chance of a better response.

the only way i see horse power gains are possible is if your super charged or turbo charged. other then that i see no hp gains, and if there is some like in my case itll be at 2hp gain

damn, that sucks, i was thinking that i'd have a greater hp gain. makes sense, my friend has a wrx, took of his cats, and there was a considerable gain, also with a gs-x (no cats) and it was considerable. oh well, there goes that idea.

i took off my cat a couple of months back...the pipe is 3" (towards the header) around one side and 2" on the other...neways i never did a dyno on it or anything coz from where i'm, there are no such machines...however after i took it off...man i DID feel a difference...20hp that i guess is a little too far fetched...nehow i'll pick driving the car without the cat any day...and abt the engine check light...it never came on...

removing the cat does give you better gains.with the cat removed and the installation of a 2 1/2 inch custom mandrel bent pipe all the way back to a canister style flow through muffler you should see anything from 10 to about 18 hp.the check engine lite might or might not come on,but lean more towards it will.you can buy one of those devices that send the signal of a perfect working cat to the ecu.

18 HP from an exhaust? i highly doubt that..no matter what piping you use.

our cat converters are already high flowing enough, so you're not gonna see much of a gain.

Watch out for law enforcement. Some of the tall tale signs of a straight pipe is the excessive amount of hydro carbons that will stick to your rear bumper. You'll notice you'll have a bunch of that black stuff all over. The air nazis will have a field day with your ass

Isnt that what the TRD Kaszuma(however you spell it) is? They claim a 20 hp increase, though they dont specify bhp or whp. ( I assume bhp)

20 whp they claim..but thats not true. same with the TRD exhaust..they claimed 14 HP gains, but realistically(dyno proven) they will average about 4-6 HP to the wheels

actually TRD claims are true, dyno proven. They might not give but 4-5 whp peak hp, but look around 6k rpm and there is 14hp improvement. As for taking off the cat, althought the improvement might be nice to have, personally i would prefer to breathe clean air. Please buy a high-flow cat instead of taking it out, i also believe ours is already high-flow as already stated. Just buy a trial header and you'll get similar gains!