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Is A Cat Really Needed?

Ruxis

By Ruxis,
in Engines & Forced Induction

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Ruxis Veteran

Ruxis

Posted
Posted

Hey guys,

Hope I don't get flames for this one,

Is a cat really needed?? I have a gtt and on it I have the regu 06 Kakimoto catback with a 3" split dump/front pipe. With the stock cat.

What gains will I see from getting say the catco 3inch high flow cat?? Someone told be it's good to have back pressure, but you guys seem to live by having the best flow possible.

Plus will the catco be legal emission wise???

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r33_racer Grand Master

r33_racer

Posted
Posted

The less back pressure the better.

You could always just gut your standard cat if you dont want to goto a high flow unit. But its a risk if you get caught. A highflow unit shouldnt be illegal, but it is NSW so you really need to check your local tpt laws.

boostn0199 Grand Master

boostn0199

Posted
Posted

Depends on your power level if the cars relativly stock you wont really feel much differce but its also nice to finish of the exhuast. If your cars not to modded juat gor for ceramic catco hiflow cat or something.

Cowboy1600 Grand Master

Cowboy1600

Posted
Posted

No CAT!

THE HORROR! That would make your car.....UNROADWORTHY!!! *cue dramatic music*

I don't want my family being killed by some foolish person who doesn't have a CAT on their car!

THE SHAME!

Sorry, I couldn't help myself.

greensa14 Collaborator

greensa14

Posted
Posted

At the end of the day ya car is probably illegal is some way. Spend the $170 and get a highflow, or spend $50 and run a decat. Its your choice. BUT.........if you got done for emissions your highflow would not pass so it is safe to say that you are unroadworthy anyway.

If it is yuor daily, i would suggest being as legal as possible.

If it is your weekend toy........thats a different story.

Ruxis Veteran

Ruxis

Posted
  • Author
Posted

Nah I'd like to keep it as legal as possible, plus I like to collect my stock parts for such a day.

I'm running "turbo back" exhaust with the stock cat lol. Air filter and 10 point boost. That's basically it. Much increase you think??

They can send you for an emissions test under suspicion can't they?? So even with a catback and everything stock you could be in the same position??

If it's going to be an upgrade I'll do it but if it's minimal I probably won't bother.

Ruxis Veteran

Ruxis

Posted
  • Author
Posted

Nah I'd like to keep it as legal as possible, plus I like to collect my stock parts for such a day.

I'm running "turbo back" exhaust with the stock cat lol. Pod filter and 10 pound boost. That's basically it. Much increase you think??

They can send you for an emissions test under suspicion can't they?? So even with a catback and everything stock you could be in the same position??

If it's going to be an upgrade I'll do it but if it's minimal I probably won't bother.

pistol-pete Veteran

pistol-pete

Posted
Posted

if they send you for a test, just swap out the decat before you go. if youre still running the compliance cat then removing it for either a high flow or a decat will make a difference.

Blitz Grand Master

Blitz

Posted
Posted

the only way youre gonna get caught without a cat is if youre foolish enough to go through an emissions test without one.

............or, if you happen to be unlucky enough to have a Police car behind you at night and they see flames shooting out of your muffler >_<

Blitz Grand Master

Blitz

Posted
Posted

They can send you for an emissions test under suspicion can't they?? So even with a catback and everything stock you could be in the same position??

Short answer, if they suspect your car may not be EPA compliant, be that for noise output or emissions, then yes they can defect you and send you to the EPA.

By the sounds of it on your lightly modified car there is no massive gain to be had running no cat - If your car was pushing out 400kw and you had a serious exhaust restriction then it might be a different story, not to mention that the fine for being caught with no cat is around $10,000 from memory.

pistol-pete Veteran

pistol-pete

Posted
Posted

Short answer, if they suspect your car may not be EPA compliant, be that for noise output or emissions, then yes they can defect you and send you to the EPA.

i realise that but my point is if youre sent for a test, just put the stock cat back and pass it. they cant give you a $10,000 fine on the side of the road. also afaik that big fine is only for workshops no?

Blitz Grand Master

Blitz

Posted
Posted

i realise that but my point is if youre sent for a test, just put the stock cat back and pass it. they cant give you a $10,000 fine on the side of the road. also afaik that big fine is only for workshops no?

That will work if you are pulled over and sent off for an EPA test, however if you are unlucky enough to get caught in a joint Police/RTA/EPA defect setup then its a totally different story, so while you'd have to be VERY unlucky to get pulled in to one of the full house setup's, the fact is it can happen, and you may have a tough time trying to talk your way out of it to an EPA official when they have your car strapped to a dyno at night to check the noise and it starts blowing flames out the back.

I think you will find that the EPA can fine you on the spot just as the Police can.

Harey Veteran

Harey

Posted
Posted

I would strongly recommend a 100 cell metal cat, I bought mine from Venom and it was only $60 more than a ceramic 200 cell cat from just jap or others. Venom can sell them with the factory flanges so it just bolts on.

That will mean that you cant get an on the spot fine as you have a cat. If you do get sent for an emissions test I would still recommend changing it back to the standard one though to be safer.

Hanaldo Grand Master

Hanaldo

Posted
Posted

Yeh we have the road-side tests here too, but they don't strap you onto a dyno. They just have emissions and noise testers that they use while your car is idling and they rev it to 5000rpm in neutral.

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