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5 Gas Test And Cat Converter

Sizygy

By Sizygy,
in Engines & Forced Induction

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Sizygy Apprentice

Sizygy

Posted
Posted

Hey guys, I know this is a done topic but im searching for an answer from people who have done this, anyway, I'm in WA with an r32gtr, took it over the pits and have to get it engineered, which means a 5 gas test.

I went over with cams and failed hard, so am going back to stock for for the test and some id1000 injectors and tune to suit.

Where I am struggling for a definitive answer is on on the Cat converter, I 've been reading and am unsure, people are saying stock ceramic cat, so are a couple of shops but 2 other shops have said to go something like a 400 cell euro 4 cat.

I don't know much about this so can anyone that has passed with a similar setup share their experience with what cat would be better or if there are any better ones to go for that would be much appreciated.

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https://www.sau.com.au/forums/topic/403635-5-gas-test-and-cat-converter/
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abr33 Proficient

abr33

Posted
Posted

Depends on the tune, too rich will fail, too lean will fail.

I do happen to know what will make you pass. I did IM240 test here in NSW, presume similar test.

I got the cat out of a new bf xr6 turbo, and made it fit my system. its 3" in and outlet.

It was literally running euro 4 standard at most points of the test.

A normal cat will not flow real well compared the the massive substrate in the falcon cat, in which it has enough time in the substrate to properly convert.

Keep in mind, the newer the better. Even a new cat thats had a bad bit of fuel burnt, or slightly poor/rich/lean tune will have glazed the substrate and be useless.

I did this after epically failing with x-force cat.

Stock ecu also.

TiTAN Grand Master

TiTAN

Posted
Posted

Ok thanks, good info, I think the 5 gas is a little more lenient than IM240, ill ring a couple places tomorrow about an xr6t cat. I'm running a vipec ecu.

*edit* abr33 is that with and Rb26 and stock injectors or a 25?

i passed the IM240 with a euro 3 cat (euro 4 will be better), 740cc injectors, gt35r, stock cams (big cams will hurt your results), running off a vipec plugin. if its tuned for emissions with a good cat is possible to pass with a fairly modified car.

rob82 Mentor

rob82

Posted
Posted

Most three way Catalytic converters need the tune to be close to stoic in order to keep the cat at elevated temperature and to aid in the reduction of your three gases. This will be difficult with 1000cc injectors. I would also recommend using std 370cc injectors or similar.

Moodles2 Grand Master

Moodles2

Posted
Posted

If getting a cat, stick with Catco or Magnaflow as these will actually pass an emissions test. Catco have had their's tested with the EPA and have certificates for them whereas knockoffs (X-force which is a copy of a HKS cat for example) don't have a chance in hell of passing. Magnaflow being american and Californian emissions laws I think being even stricter than Euro standards.

TiTAN Grand Master

TiTAN

Posted
Posted

thats probably just something they do so its almost guaranteed to pass first time but running 5 cats isnt practical or cheap and you have to get them all up to temp before they work properly anyway, they should always do 2 tests when checking, you will notice the first test is almost always a fail as the cat isnt at operating temp and then they do a 2nd test which has massively improved results as your cat has got some heat into it.

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