cptpain

iTrader: (1)

I am buying a bone stock FD next week and am buying a TBE setup for it.


I am either going with the rx7store DP or the Bonez offered at Rotary Performance, a high-flow cat, and the Racing Beat Dual tip catback.


What bothers me tho is the fact that those who have the high-flow cats, all have the stainless steel HFC and there are plenty of threads over the years that i've been a member on here, and read that the SS HFC wont last very long, and that the Ceramic type HFC will last much much longer.

Where can i get one of these ceramic HFC from?

I want something that is going to last and not degrade over time. I am only going to have this setup for about a year or two while i save up for a brand new shortblock from Malloy, and start my 35R build.

This way, i can sell the bolt-on stuff to try a recoup some money for a tune.

If nothing comes up in the next few days about a ceramic cat, then ill take the loss and go with the bonez

thewird

iTrader: (8)

http://randomtechnology.com/products.html

thewird

cptpain

iTrader: (1)

while on the subject of exhaust.....

where can i find the RB SINGLE tip exhaust?

Ernesto13B

iTrader: (4)

Actually that's backwards. The metallic substrate converters will withstand more heat and abuse then the ceramic ones do, and wont clog. Also the metallic internal material wont break down eventually like the ceramic does.The reason why a lot of ppl go with the metallic, is that they can withstand richer fuel mixtures and abuse without degrading, and they flow better.

However, ceramic converters will clean emission better than a metallic one. This is why Mazda used a Metallic Substrate for the precat so it cant degrade over time, but for the main cat they used a ceramic converter, because it cleans up emissions a lot better.

I'd recommend the ceramic cat.

cptpain

iTrader: (1)

it seems i really did have it back-asswards this whole time..... thanks Ernesto!

BTW, there is no emissions testing where i live so im not worried about it, im just worried about the droning/obnoxiously loudness i would get if i run cat-less.

could i essentially ditch the cat and just get a resonated midpipe, if my primary reason is noise? or would the R-MP just be a touch louder?

gracer7-rx7

iTrader: (16)

Get the Bonez for a good high flow cat. Adding a small metal substrate cat does very little or nothing at all for sound abatement. Been there done that, read my old posts on the topic if you want background.

SMB has a cool mid pipe setup that has both a metal substrate cat and a muffler/resonator in the same section. That does work for sound abatement and decreased stink. No one else makes such a pipe so you can either roll your own or get it direct from SMB in Australia.

The life of the cat really is mostly a factor of tuning and setup. Traditional ceramic cored cats for the FD usually require fresh air injection to get the core up to temps to be able to work more effectively and not clog up the substrate. Metal cats don't like that extra air. The chemicals and materials work differently.

Tuning (AFR levels), fuel leakage into the exhaust stream, too much oil in the exhaust stream will all lead to a premature death.

The above is all based on my direct experience, not opinion. I never had an issue with a metal core cat.

Natey

iTrader: (19)

For the RB single-tip, Goodwin Racing has always treated me great.

http://www.good-win-racing.com/Mazda...art/16426.html

arghx

iTrader: (3)

My experience with metallic substrate cats is that they are best for cleaning up the smell under low load driving without causing a great restriction in the exhaust. They're not the best for passing emissions tests.

arghx

iTrader: (3)

The metallic substrate operates better at lower temperatures which makes it better as a precat.



But the clogging rate of the stock metallic precat is pretty high for whatever reason, although that may not necessarily be caused by the metallic substrate itself. Ceramic converters work better at the temperatures and loads normally used in emissions tests.

The other thing to keep in mind is that aftermarket converters don't have the same amount of expensive catalyst material in them (like platinum) which is one of the reasons why they cost less and run dirtier than OEM cats.

See https://www.rx7club.com/showpost.php...6&postcount=34

Either way, OEM is always the best to pass emissions tests. That's one of the reasons why they are so expensive.

Mahjik

iTrader: (1)

So far, the standard "off the shelf" metallic substrate converters do not last long on FI rotaries. You can find many threads in this section about failed metallic substrate converters. There hasn't been much information on the Knightsport metallic substrate converters, but most others have been rendered useless within a little over year.

If you want something that is proven to last, go with the Bonez products. I ran one for many years.

cptpain

iTrader: (1)

What other exhaust pieces have you used along with the Bonez piece, and how did all of it fare for droning?

Thank you for the input, that piece is very nice but way out of my price range/budget for an exhaust.....

BUT, could i add/fab a midpipe that would come after the HFC to reduce noise even further?

Dude you're awesome!!! thanks a bunch for finding this for me!!

no_more_rice

Cats don't last in these cars, they're a complete waste of time and money. There is MASSIVE blow-by of unburned fuel with any turbo rotary, and no cat can tolerate that for long, regardless of what anyone claims to the contrary (such people put few miles on their cars). It's akin to the days when Yamaha tried to put cats on two stroke waverunners; all of them clogged.

Put a resonated mid-pipe on and let it rip. CA? They're broke anyway, who cares about their stupid regs.

Natey

iTrader: (19)

I'm not broke, and I care since I live under Cali laws.

adamrs80

iTrader: (7)

I think this may be about to change. I'm in San Antonio and I heard last week on 1200 WOAI that the EPA with the TCEQ are raising the standards for air quality to a point so high that the air in the grand canyon would not meet the new spec. That is pretty much verbatim. A total crock but a definite possibility. Inspections go from $14 to $40 and we get the pipe sniffer. I despise the government and all the recent green bullshit. We're not warming out houses by burning tires.

Mahjik

iTrader: (1)

At the time (around 2000), I had installed the Bonez DP with the Hi-flo and the Greddy Power Extreme catback. The exhaust note of the combination was quieter than my buddy's car which was BNR Stage 3 twins (original design) with a DP, resonated MP and Racing Beat dual catback.

moconnor

iTrader: (14)

Empirically, this claim is false (the stock cat or the Bonez appear to last for 100k+ miles and I have not seen a quality metallic cat failure post in years).

Perhaps making apparently controversial (though, really, just false) pronouncements gives you a kick - but I would recommend spending at least four or five years on this board before making them. Otherwise, you will just come across as the type of person that likes to be controversial for the sake of it.

cptpain

iTrader: (1)

Lets try and keep on topic; but just to touch on it....

Texas EPA laws are BY COUNTY AFAIK..... So in my county there are NO emissions tests whatsoever, not even a visual. Just a $14 inspection and im g2g

cptpain

iTrader: (1)

Hmmm, seems like this is exactly what i needed to hear. Thanks a bunch

no_more_rice

No, it's not false

The stock cats don't last 100k miles. Provide a fluke example that did and I'll list 100 others that didn't. Your claim is empircally false based on overwhelming statistics

What does that prove? How many miles?

I've been here longer than you, 9 years to be exact.

Sgtblue

iTrader: (16)

Your first statement is.
My Bonez has at least 65k and 8 years on it. Plus whatever the previous owner put on it. Still flows well and no indication it's even close to wearing out. And my experience seems to be the norm, not the exception.

moconnor

iTrader: (14)

'Overwhelming', huh? And you really have a list of 100s of failed cats?

Seriously, dude, stop talking *****. If stock or Bonez cats were such a failure item there would not be such a used market in them. Find me a failed FD cat and I'll bet its brand name is Magnaflow.

It really does not show. Your ideas and opinions reflect the state of knowledge of FDs in 2002. A properly running FD does not: (1) destroy its cat; (2) have trouble passing an emissions test; or (3) need a mid pipe to perform well. Next, you will be touting the benefits of turbo timers, piggy backs, and the K&S knock sensor.