Getting a high flow catalytic converter?
 

Whats the best high flow catalytic converter you can get for a 2nd gen RX-7?

A straight pipe. :)

If your state still does emissions testing for the 7, I'd look on rx7.com or racingbeat to find something acceptable for what you are trying to do.

Also for the record the cat is not the restriction-devil that many would have you think, unless you're planning on installing a full engine-back system I wouldn't bother.

it is the single largest restriction of power on these cars.

metallic substrate cats are the most efficient for airflow but coversely the least efficient at actually doing the job of cleaning up emissions. that is the main reason why they are banned in california.

Aha... maybe that's what I was gettin at. Is that what these high flow cats on the speed shop sites are made of? (not a concern of mine really as I run a straight pipe)

most "high flow cats" or "race cats" are simple presilencers/mufflers from the speed shops.

i have no idea who started it or why, it's a misconcept and actually a lie because they are not catalysts(cat) AT ALL!

avoid anything called a race cat, it's not a catalytic converter at all. many places still refer to high flow cats as presilencers also so be prepared to ask questions and cover your ass.

Karak,

To be fair, the guys at RX7.com hold the design and used to produce (perhaps they still do) a high flow cat specifically for the requirements of an RX7. The generic "high flow cats" at indeed glorified presilencers.

Random Technologies cats. spendy, but good.

never said all suppliers do, ebay is obviously the worst for terminology. look up a race cat on there and you'll get hundreds of hits for test pipes and mufflers. it seems to be decreasing slightly, probably because of all the unsatisfied customers bitching to ebay and getting sellers banned.

so putting one on which would replace my resonator would actually make the car quieter? im looking for the opposite. i want my car as loud as possible

I hope this isn't your daily driver then for many reasons.................

nothing after the manifold will be as loud as possible. let me know how long it takes before your first fix it ticket.

there was one kid who showed up at 7stock a number of years ago, don't be that kid.

+1

Put one on a big port 13B, flowed great(I have a flow bench). Shortly after we bought it Florida got rid of emission testing all together.

They had it in certain counties for a number of years and you would see cars tagged in all kinds of other counties driving around the cities and parked in driveways every evening, hmmm, wonder why that was?

Details?

He literally f_cked it up for everyone else. Stupid dip s_it!!:icon_tdow:icon_tdow That sort of SH_t is exactly why the 7Stock organizers had to run around and figure out how to save 7Stock this year.

Wow... I have a feeling he was a teen then? I mean I'm only 18 but I still am mature enough for this to be a hobby and not a OMG LOOK AT ME I LOVE FAST AND FURRUS driver or type of person. Really a shame that one person could ruin such a respected event...

he had some moronic stickers on his car "smogpolluter" or some shit like that, had straightpiped exhaust and was racing his car around the side streets before the event.

the car sounded like complete ass because of the lack of any muffler whatsoever, it was a very poor example for the rotary community and made me a little ashamed to own my car.

this was back during SS7 or 8, i can't recall which exactly. the stickers made me think that his intention was to give the cars a bad name along with his zip tied together dash and gutted interior. the car was slower than stock btw, due to the ill performed modifications. made me think of the majority of honda owners. hopefully he blew up the motor and disappeared because that was the last i saw of it(perhaps reffed/towed because the sticker was to a website called smogpolluter.com), but i do recall the name on the forum around that time as well.

the kid was just a straight up attention whore, that is all.

Smh, smh....

I run a magnaflow cat on my 7. I couldn't be happier :) Passed emissions with flying colors, and the exhaust tone is well reserved. Not sure how much they adversely affect air flow, but from a lot of people I talked to, (some even did flow tests) CATS are far less restrictive than they used to be.

you can google it (i did!) but factory cats need to have a density in the 1200 somethings per something area, but aftermarkets are 600, so there's less "stuff" in an aftermarket cat, so basically every aftermarket cat is high flow.

if you compared the core size of the stock cat with the after market you can see that the factory cat is also way bigger.

the metallic cat flow more because the substrate is thinner than the ceramic

^^ true.

i have a 2.5 bonez high flow cat (from rx7.com) to a 2.5 corksport exhaust, sounds great, gain a few hp and not to loud or annoying. gonna get a rb hearders and test pipe cause it sounds real nice, not as loud as i thought and get some good gains too

Gotta love all that technical tawk. :nod:

hopefully i'm not thread jacking, but being that the op has an S5 he doesn't have to worry about that mid pipe with the back pressure tube for the ports, forgot what its called, but having one of those also helps in quieting down the car?

:) i'm a blonde... its a lifestyle...