Best Affordable Catalytic Converter
 

Hi,

I was just wondering what cat's you guys had, I was looking into the Bonez stainless steel, or the SR motorsports cat. I have to go through inspection very soon. So I'd appreciate any feedback. I ran some searches but didn't find anything definate.

If anyone has or has had experience with either cats or any other brand please let me know.

Thanks,

Mo

whatever you do dont buy a cat pipe that uses a "catco" brand cat.

I haven't used one, but why do you recommend against Catco cats?

-Max

The company I work for's exhaust bender switched from magnaflow to catco brand cats in the pipe without notifying anyone.

I think just about every one of the catco cats that went out was returned because it broke up and we had to send them replacement magnaflow ones. Obviously the use of the catco cats was permenantly stopped. Ive never had a problem with a magnaflow though.

Mike

need a pipe?
 

Hey Mo,
I had the hi flow cat from Petit, and didn't have any problems. Since I live in NV with no inspection I went with the midpipe and took the cat off. I can give it to you for 200 plus shipping. I already have a box for it so whatever the postage is. I also have a bonz downpipe I can give you for 150.

tigerdriver, I've been looking for one, if project doesn't want it i'll take it!
give me a pm

Matt

Hey TigerDriver,

I'll take the cat. Pm me with all the details im very interested.

Thanks,

Mo

Good to know. Thanks for sharing your experience.

-Max

If I'm not mistaken, doesn't Pettit use Catco cats in their high-flow cats?

http://www.pettitracing.com/rx7/prod...st_312-600.jpg

Pic of my Catco universal cat:

http://img.photobucket.com/albums/v2...s/PICT0013.jpg

I don't recall anything negative about their cats?

I got the Bonez hi-flo from rx7.com on my FC a couple of years ago and more recently on my FD. Passed CA smog no worries (with downpipe) also without any tricks (like alcohol, etc). Seems to do the trick pretty well.

Simon.

I had a Pettit high flow cat. It lasted for about 6 months and then the stuff inside blew out the tailpipe. Now I have a midpipe for free. The guy behind me was pissed.

From an old post:

Might not be considered affordable.... but we should wait and see some [real] results from the few Metalit cat users out there. If they can show that they dont get blown out like traditional cats... they maybe worth the money.

I run really rich with a Pettit Unlimited, and I've blown out the internals of a bonez (2yrs+)and N tech (~8mos), but to be fair both were bought "slightly used." I'm just using a stock cat for now til I can buy a hi-flo unit with confidence.... and tune my car properly.

We use Magnaflow in our high flow cat and havent had any problems
http://www.rx7store.net/index.asp?Pa...ROD&ProdID=312

Jason

Interesting. Something else must have been wrong as I ran the Pettit ECU and the Bonez DP & Hi-Flo for 4+ years (one of those years without the airpump). When I sold the cat last year, it was in great condition.

fwiw - when i was talking to Random about their metal substrate cats, they said that the primary reason cats fail is due to overly rich mixtures.

Hey Jason, does your kit come with everything to hook up with the air pump?

Our cat does come with the airpump pipe off of the cat. The only thing you need to do is run the hose to it.

Jason

FWIW, BONEZ here. It came with the car which I've had for about 2 1/2 years. No problems, but I can't compare it to anything else.

Running too rich can basically burn out any Cat really.... fuel is what heats them up more. A good way to test a functioning cat is to pull a plug wire and get an infared temp reader. Measure before and after the cat., and there should be at least a 100 degree increase after the cat.

What do you use for the hose, I tried high temp rubber or something but it just melted. Some kind of metal pipe?

I'm presently in the same boat. I just failed inspection and have probably less than a week to find a replacement for my Cat. The stock cat that is on there right now, I just found out is punched and miserably failed the sniffer test. Seeing as time is a factor, I'm looking for something quick and fairly inexpensive to just bolt up, re-take the test, then undo afterwards.

Excuse the stupid question here, but the picture linked by Jason of the High Flo Cat, is that whole thing the cat con? Or is it just the welded piece in there? Meaning, if I were to go to my local auto store and purchase a new cat for the FD, would it be the entire pipe as shown? Or would it be just a generic thing I'd have to have welded in there?

Jason is selling the entire drop in replacement. You can purchase just a catalytic converter and just have it welded in by an exhaust shop.

The benefit to getting something like Jason is selling, is that it will be a full 3" all the way. The stock piping is around 2.5".

Ok, that's what I needed to know. The thing that worries me slightly is I'm not sure the hi-flow will pass the sniffer. My HC's were waaaaaaaaaaaaaaay out of spec (1453 vs the standard passing 220----not sure why, hope something else isn't wrong). I'm going to put the stock air box back on as well, hoping that that will aid those numbers.

Thanks for the reply Mahjik. :)

No problem. Make sure everything is working properly (i.e. airpump, ACV). I've read about people in CA passing with a DP and the Bonez Hi-Flo cat (which is what made me purchase it years ago).

I don't know if NC is more or less strict than CA, but you should be fine with a hi-flo cat as long as everything else on your car is working properly.

Ok. I know that NC is less strict than CA (isn't every state? :p: ). I'm trying to search for HC numbers from other failed people's cars so I can get an idea if something is REALLY wrong or if it's just the punched cat (cause my number is REALLY huge and that worries me that something else is wrong).

Again, Mahjik, thanks for your input. You're helping me out a great deal here and I really do appreciate it. :bigthumb:

Don't go for longevity - after 1/1/06, pre-OBDII cars in NC only have to pass visual/safety inspection (no sniffer).

The stock cat has 2 1/2" piping. However, the flanges that are welded to the inlet and outlet, are welded on the inside. This reduces the opening and exit diameter of the cat to about 2 1/8". That is a 27% reduction in both openings, and is a significant restriction.

There is a simple and inexpensive mod for this. Remove your cat, and re-weld the flanges on the outside. Any decent welder should be able to do this quickly, and inexpensively. My neighbor welded them for me, so all it cost me was a few beers :) After the flanges are welded on the outside, you can grind down the inside welds to a nice smooth finish. It is important that you weld the outside first!! You don't want it coming apart.

I did this on my car, and was able to feel a small increase in power. Definitely worth the time spent. Now I have a "higher flowing", smog legal stock cat :D

ive got a metalit cat (but i havent put many miles on it yet... maybe like 6000 mi?). anyway i really like the cat, but the price was a little steep. IIRC, that was the cat i was running when i passed my last CA nazi-smog test. the cat warms up in about 15-20 seconds it seems.... and if i stick my nose up to the exhaust all i can smell is hot air. it also seems to flow pretty well... and i ended up porting my WG to prevent any boost creep (last time i had the turbos out). that being said, im a bit worried about the lifespan of this cat. the metal substrate should last much much longer than the ceramic ones... btu the way that the metal "foil" is rolled inside (and the thinness of this foil) makes me worry about the consequences of backfires leading to mis-shaping the delecate foil on the inside.

who knows... we'll see how long it lasts.... either way, ill be running one (or possibly two) of some sort of metal substrate cat on my 20b FD (be that the knightsports one or a generic metal substrate one) as i really like its effectiveness at scrubbing the air as well as the decent flow charachteristics. JUST SAY NO TO MIDPIPES!! they freakin STINK and smell up your clothes and hair, are bad for you to inhale, and most importantly are bad for the environment! i dont want to be responsible for destroying our air quality so i can squeeze 5 extra HP out of my ricer fart can. if you want a car w/out a cat get something from 1965.... otherwise just use a cat. if its good enough for my 20b, its good enough for you :biggrin: ! -heath

(PS id be happy to answer any q's about the metalit/knightsport cats... and can also direct you to some of the generic ones that just need to be welded in and are much cheaper.. feel free to throw a post or a PM at me. later)

have anyone taken the stock cat and have it modified with 3 inch pipes?? I thinking about this mod...