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im looking for a good 3inch cat to replace my current 2.5inch one.

this Catco cat :http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=4638457419&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1

which claims better flow than metalcat or magiccat but dearer in price.

the metalcat:http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=4636343498&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1

looks alright, seems to be the right price for a good quality free flowing cat.

or i can go for a cheap cat like this one:http://cgi.ebay.com.au/3-HI-FLOW-CAT-NISSAN-Skyline-Silvia-Intercooler_W0QQitemZ4630800720QQcategoryZ43807QQrdZ1QQcmdZViewItem

as long as its straight through and provides better flow than my current 2.5inch cat.

what are you thoughts on this?

cheers

Edited by Forged

what paul is trying to say is that the difference between the "best" 3" cat and the "worst" 3" cat is going to be about 2rwkw on the dyno

so as long as its 3" in internal diameter, and it has cat material in it, then don't worrhy about what you are getting

Warren

what paul is trying to say is that the difference between the "best" 3" cat and the "worst" 3" cat is going to be about 2rwkw on the dyno

so as long as its 3" in internal diameter, and it has cat material in it, then don't worrhy about what you are getting

Warren

alright thanks guys i guess i will just go for the metalcat for its ADR approved.

cheers

AFAIK Jasma (Japanese Automotive Sport Muffler Assoc) isn't a brand, its an association to state compliance to exhaust regulations.

JustJap has 3" cats for like $160, unless you're aiming for a lot out of the car i doubt you'd notice any difference.

Surely the cells per square inch plays a part in flow?

And what about ceramic vs metal catalysts? From my own experience, bad tuning has melted ceramic ones shut. One to the point it was literally restricting flow to the point it blew a hole in the top of the cat

Get a cheap one and ram a pole through it. The highest flowing cat on the market.

On a more serious note I believe the Metal Cat and Magic Cats are the highest flowing on the market, but on a lower powered car theres a bees dick difference between all 3.

AFAIK Jasma (Japanese Automotive Sport Muffler Assoc) isn't a brand, its an association to state compliance to exhaust regulations.

JustJap has 3" cats for like $160, unless you're aiming for a lot out of the car i doubt you'd notice any difference.

haha thanks mate, i always thought thats the brand of my exhaust (the only tag on the muffler says JASMA)

Get a cheap one and ram a pole through it. The highest flowing cat on the market.

On a more serious note I believe the Metal Cat and Magic Cats are the highest flowing on the market, but on a lower powered car theres a bees dick difference between all 3.

i know theres only less than a few kws difference on the dyno but i dont mind spending a little extra cash for a good quality product just for peace of mind.

metalcat claims true 200cell[less cell the better] where as most others on the market are actually 300cell. a normal 3" system flows 589cfm the reduction through metal cat is only 10% down to 534cfm.

anyways that what there claiming i will never get the chance to confirm these though.

post-23968-1147268518.jpg

  • 9 months later...

an update on what i ended up getting. 3" Metalcat from ebay. on a dynojet dyno the car made 266rwkw with a 3inch cat-bypass pipe and 260rwkw with the 3" Metalcat. not bad for a local made cat i think. what do you think?

id spend the lil bit extra and get a brand name cat rather then a dodgy one, only reason being is i reakon it would last longer as ive seen cheap ones come loose internaly and cause a shity rattle... id say a brand name one without any impact damage would last longer if anything

I read an articel in a HPI mag saying quite the opposite of what has been previously stated.

A stock exhaust with good metal cat made more power than a big aftermarket exhaust with avg cat.

Basically claimed that diameter of cat back makes no difference and no advantage over the std exhaust on the bnr32, and all power will come from a quality cat.

Edited by neergnevets
im looking for a good 3inch cat to replace my current 2.5inch one.

this Catco cat :http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=4638457419&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1

which claims better flow than metalcat or magiccat but dearer in price.

the metalcat:http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=4636343498&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1

looks alright, seems to be the right price for a good quality free flowing cat.

or i can go for a cheap cat like this one:http://cgi.ebay.com.au/3-HI-FLOW-CAT-NISSAN-Skyline-Silvia-Intercooler_W0QQitemZ4630800720QQcategoryZ43807QQrdZ1QQcmdZViewItem

as long as its straight through and provides better flow than my current 2.5inch cat.

what are you thoughts on this?

cheers

as long as it is a metalic hiflowed cat u should get good gains mate :)

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