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gutting cat converter

Guest TUFR33

By Guest TUFR33,
in Engines & Forced Induction

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GTS-t VSPEC Grand Master

GTS-t VSPEC

Posted
Posted

If you have a hi-flow cat then the piping should be 3", if you can managed to weld a piece of 3" pipe inside the cat then it wouldn't be restrictive at all. There will be a small performance edge in doing this, but may not be worth your while unless you have a high-horsepower car.

See'ya:burnout:

Merli Grand Master

Merli

Posted
Posted

Please please please don't do this.

It's really bad for our environment, makes your car smell like sh1t, and you can cop a $10,000 fine for it...

Plus unless you have a highly, HIGHLY modified car, you won't gain more than 5-10kw, and that's being generous.

Merli Grand Master

Merli

Posted
Posted
Originally posted by Duncan

Run NOS, the fine is cheaper and the increase larger

AAAAAAAAAAAHAHAHAHAHAHAHAHAHA!!!

:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:

GTS-t VSPEC Grand Master

GTS-t VSPEC

Posted
Posted

Works,

Did you notice any difference in performance? I'm planning on doing this cause I'm going to run rotational idle, but I'll still have something which looks like a cat for the cops. I can't imagine that the fumes would be much worse either.

See'ya:burnout:

torana_mad Community Regular

torana_mad

Posted
Posted

Due to the age of my car i dont have to run cats (thats what rta said because i did check as the cat adr came in after the yr of my car) and the only time my car smells is on warm/start up.

As Andrew said it is a big fine for a few more KW and it will stand out as all hell if a cop spots the flame out the ass end of your car.

Yes the flame looks dam good but is it worth it in the end? :)

If your going to worry about the environment sell your car and buy a push bike ;)

If your going to the track get a pipe section made up so you can remove the cat (would take 5mins) if it worrys you that much and swap it back to the cat for the street.

ph1 Rising Star

ph1

Posted
Posted

definately a louder, crisper note. droning is caused by mufflers/resonators or anything that impacts the flow of your exhaust gas, so removing the cat is more than likely going to reduce the drone of your exhaust.

environmental issues is the usual argument that comes up when mentioning removing cats. fact is... catalytic converters have a limited working lifespan, which is approx 100,000klms for oem units, and usually less for aftermarket items. how many cars on the road do u think replace their catalytic converter every 2-3 years? yep, none. unburnt fuel can also melt the core of the catalytic converter. so those guys with huge camshaft overlap, or running insanely rich mixtures (which will include most ppl with skylines :)), will more than likely have an almost useless cat anyway.

headaches? doubt it, more likely to be an exhaust leak somewhere under the car, maybe the gutted cat wasn't reinstalled with the gaskets?

other than the possibility of a fine, i personally cannot see a reason to not remove your cat... (that is unless it's just for the flames :) )

summoner Mentor

summoner

Posted
Posted

been tempted to do it with the ute, i used to run hi flowing cats on my auto ute and it had bulk top end mumbo :P

Might get some Cat replacement pipes made up for "drag" usage and then just get my spare set of cats, remove the cover and get put it around the pipe so when i drive to and from the drags i dont get cop hassles :)

For me though cat/no cat is almost pointless as when cold the cats dont work anyway and by time i get to work they only just start heating up ahah..

Eitherway I'd keep 2 sets of pipes for race/drag use and for daily driving. But for fun i'd go no cat for a bit just so i can get footage of flames ;)

rev210 Grand Master

rev210

Posted
Posted

flames and quicker turbo spool up. Top end flow is increased as well.

If you look inside the catalytic it is quite a restrictive peice of work. Having a de-cat pipe or better still a flame thrower is good for off street work. If the exhaust joint does a nice 3 bolt flange and give you some spare gaskets its only a 10min job so you can stay legal on the street and go wild at the track.

Does the plex allow you to run dump pipes/flame throwers these days?

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