6G Celicas Forums

Hey guys!! I was wondering if there really is a big need for the converter. Would anything bad actually happen to the performance of the engine with not having the converter? Cuz mine's like rusted up and I'm thinkin', why not just make it a straight piping all the way to the muffler! Gimme your opinions.

if im not mistaken the cat converter actuly restricks your car its mostly used for emissions if you get a test pipe to replace the cat or just can custom piping then it should let your car have more air flow witch should give you more hp not much but its less restricting if im wrong about anything everyone feel free to give me the evil eye and correct me ......

You will be grossly poluting by removing your catalytic converter, all for just a couple horse power(if that). Get a high flow cat.

I think manufacturers like Pipercross or Mongoose make de-cats for celicas, the cat does slightly restrict the exhaust gas flow outta your car, so replacing it with a straight through section is supposed to improve lower down torque by removing this restriction. If you do do it, make sure you use a good quality metal as i hear it has a tendency to rasp if not.

You will probably need to put it back on when your car is emissions tested, as it will more than likely fail without a cat. That is the case for us in the UK anyway, and it is illegal i believe to have a de-cat if your car is younger than a 92 or 93 plate? So you may want to check into those factors before you go ahead any further As for environmental sustainability - thats your personal choice, and as dutchboy said, you can purchase highflow cats that are legal as a mid ground (i think they are popular with Gen7 owners)

Hope that helps fella

I heard that if you take the cat off, you get black marks on your rear bumper, because the pollution (or whatever it is) isnt taken out of the exhaust stream... just what I heard, I dont know if its actually true. I would just get a high flow one though.

Ale Gore is gunna be pissed if you take it off.
only you can prevent global warming...

Actually a cat can cause you to loose up to 10% of the power of a car. On some cars it is actually more environmentally sound not to have a cat and hence burn less fuel - unless you still press the loud pedal the same amount and just go faster of course

My cat actually spit it's guts out and the car still passes UK emissions.

As for what VinceNoir said about UK rules - 92 if the car is listed in the EG database. If it is a JDM import it has different emissions equipment to the UK car and although the majority of MOT stations will MOT it as a UK GT you are perfectly within your rights to ask them to MOT it as a JDM SS-II up to August 95 - the SS-II won't be listed and so they only have to do a pre cat test which any celica not passing is in serious trouble given that my 1969 beetle passes it

So you're saying i should get a de-cat then, Al?!

I'm all over it!

im running custom 2.5 inch straight pipe from the turbo back i got better flow and the sound is amazing

Thanks guys! But...I don't think I'd(We) get tested in Arkansas. At least I don't think. Especially in a small town where I live. YO.....GUYS FROM THE LOWER CENTRAL STATES IIF THERE'S ANYONE OF YOU IN HERE??? Do you(we) get tested??? Oh and about pollution! Do you guys really think there's much more we can do about it? BUT yea... I'll think about it!!!

Just because smog check is not required, doesn't mean we don't have a moral obligation to limit emissions and global warming. Arkansas is hot and humid already, no sense making it worse!

I am in Arizona, they don't require smog check except in Phoenix and Tucson. If someone wants to run a smog check without their cat, and all the emissions numbers come out lower, I'll be the first person to take my Catalytic converter off my car.

Alternately, if someone wants to send me the money, I'll do the testing with the cat off the car.

Politicians say that green house gasses from automobiles are negligible compared to commercial emissions, but our government is so bought out that no one is ever going to make the businesses accountable. The only thing we can do is try and minimize our emissions.

When my motor craps out, I will look into getting a diesel motor swap so I can run biodiesel, and give the finger to the oil companies, gas stations, and OPEC.

Seriously, I'm thinking about getting a 84 benz and mod it to run on 100% vegetable oil. http://www.lovecraftbiofuels.com/ I actually checked out this place, and saw the system working. It has a heat exchanger which gets heat from the engine coolant to melt the vegetable oil so it's not all viscus. For start up there is a special exchanger that uses the glow plugs to heat the oil for the initial startup.

But yeah... until then, I'd recommend just getting a high flow cat which increases hp while still cleaning the emissions (and passing smog) and I'm seriously considering getting water/alcohol injection to reduce the emissions and get better fuel efficiency and extra hp.

This post has been edited by king_wsk: Aug 2, 2007 - 5:05 AM

thanks ass hat my family owns a gas station and its not our fault were loosing everything we have cause of oil companies put blame where its due

high flow cat ftw

the difference on an INTEGRA between no cat and a high flow cat was 2 hp and no torque diff, If you want to pollute the world for your family and future family for 2hp, then that's your decision and conscience...

well in texas at least where i live all they do is flicker the lights check the blinkers and i get my inspection and leave....actually...i got my cat cut at the same place where i get it inspected...haha texas is great.

I included part of my post you replied to, just to be fair. I don't appreciate being called an a** hat...although it is one of my personal favorite insults. It just flows off the tongue so nicely.

Sorry your family is getting railroaded, hopefully you will be inspired to bring about change in the way we fuel our cars.


Back to topic, people should just get high-flow cats. It will be a lot less trouble than having to switch back and forth for inspections or smog checks, or when you want to sell the car.

nobody takes him cereal

Since we're on the topic, after i got my car i had a free flow exhaust installed and it was great. I'm not up to snuff when it comes to fuel but recently the country stopped supplying Super fuel. Now it only supplies diesel and unleaded. i'm not sure of what the octane is on the unleaded because all of the pumps are still marked with the super stickers.

how much of an effect will this fuel have on my hp and should i consider installing a CC? and before anyone mentions inspections and global warming, remember, i'm in Africa. third world counties have not implemented smog tests or any vehicle inspections other than that it runs. But I'm not sure about South Africa, which is the most developed country in Africa.

Yo Arkansas person here. No we don't get smogged nor does the cops check us for cats either. If they did those
old chevys and ford would all be screwed considering how they V8's pollute like no tomorrow. Pollution is not much of a problem in Arkansas cuz "Its a Natural State" (my a55)

Its much more effective to have a test pipe especially if you have a JDM motor cuz they don't have a smog system like the USDM models.

Expect to shoot some nasty fire-balls when your misfiring if your missing a cat.

My JDM SS-II is actually a 1996 model - and it failed today on emissions - so do you think i can get away with letting them know it is not a UK GT? If not how much is a new replacement usually?

This post has been edited by san0: May 8, 2010 - 3:10 PM