I have looked around but found no answers. In Japan do they use a cataytic converter? If they do, is it longer than the USDM catalytic converters? Because when you put a JDM header on the USDM R, you need to extend the a flange from the cat to the header meaning something is longer in the JDM market. If something werent longer it would bolt right up except for the collector size being different. I figure it's the cat or the b-pipe. I was under the impression that since the JDM market doesn't suffer from emission control, that they didn't come with catalytic converters. Please correct me and shed some light on this subject.
Thanks

 

JDM cats are smaller and the B-pipe is longer.

 

If im not mistaken, the Jdm cat is actully shorter than the USDM one, and the midpiping is longer. so if youre bolting up a jdm header to a USDM cat, and exhuast, u need that 2.5" flange. ... but one thing has me boggled.(question for someone else) ..is there such thing as a high flow JDM cat? or are they all Test Pipes ???

 

Ok where to start
Well I guess this is a good starting point The Japanese B Pipe on the ITR and The USDM GSR are the same lengths When both have a JDM Length header installed they use a 12" long cat (stock GSR cat is much longer since the header length is shorter)
The USDM ITR' B Pipe is about 5" shorter than the 2 above So the cat is Longer, it is 17" when used with the JDM Header, The stock cat is a few inches longer because the USDM Header is shorter length.

So if you have a GSR, an ITR With GSR B pipe, or a JDM ITR B Pipe (stock or aftermarket) then you can simply bolt on a JDM ITR Cat, although it will cost more money for that than it would to get a Higher flowing cat Like the Car Sound Unit I make.
Also the 2nd O2 Sensor that mounts to the JDM ITR Cat will not fit as the JDM ITRs have a heat sensor bung which is half the size of an O2 sensor Bung, So that would need to be removed and an O2 sensor Bung welded in.
If you Have a USDM ITR with USDM B pipe (stock or aftermarket) then the JDM ITR Cat would be too short by 5" and also the above O2 sensor problem.

All in all its cheaper and easier to use one of the High flow Bolt on cats, or too even make one yourself.

 

yeah... the jdm cat is this cute little thing that i think is only there to keep the o2 sensor happy

a friend locally tried to use it as an alternative to running a test pipe, but when he went to do his emissions test the car failed

 

Cool, so test pipe it is! .. do u know where i can get AIR CARE passed?

 

i don't understand the question... did your car fail? he ended up putting his stock exhaust and cat back on in order to pass.

 

JDM cat is hella cool.. i had complete piping on my EG.. got it all for 75 bucks.. cat, and piping.. bolted it right on the jdm header.. gutted that little cat.. looked just like straight pipe.. it so small and i think it works well as a test pipe when gutten of course you will not pass with gutted cat but at least no need to buy a test pipe.. i wish i could find another importer that brings in clips so that i can get it again... then all i need to buy is a header

 

I just meant, do you know any place that can pull strings, to pass your car.. so you dont have to bother putting all the stock parts back. Im new to BC so i dont really know much about the air care laws, and i dont have any hook ups. Just wondering because i know in CA where they have to pass a Smog test... there are always places thatll pull some strings for you.

 

as far as i know cheating is pretty much impossible since the emissions test is done by a gov't facility, not an independent shop.

 

i have pics of back to back comparisons of the jdm itr car and usdm itr cat. i wave to find them, then i'll post.