Would an aftermarket, non-rotary catalytic converter work on my 91 Rex? Or would it melt from the much higher-than-piston temperatures?

thanks,
Kris

 

Standard cats will not be able to handle the heat of the rotary and will last literally minutes.

 

Don't waste your money buddy. I got a used bonez superflo cat for $150 plus shipping, and that was quite possibly the best upgrade that I have ever done to my car. It is an excellent product, and the quality is superb. I was faced with the same question a couple of weeks ago, but decided to dish out the extra couple bucks to get a REAL catalytic converter

 

If one did last only minutes, would it be harmful to the engine, or would it be just like driving with a blown out muffler?

thanks,
Kris

 

bump

Will a non-rotary catalytic converter be harmful to the engine?

 

$150

Where in the world did you get a bonez cat for only $150 bucks!!!

oops I missed the word "used" in your statement.
I was jumping out of my seat for a minute thinking I might be able to get one for $150. Oh well I guess I'm still going to have to shell out $250 for a new one.

Great buy though, for a $150 used.

 

I got a dynomax from sumitt for mine $129.00

 

A lot of people use the cheap Catco cats that Summit Racing sells for $100. They last about 2 years before they no longer pass emissions. I've had one on my 88 T2 for a while now with no problems, and the exhaust still smells like gunpowder/sulfer, like a new car's exhaust smells.

The catco ones are an oem type replacement, so you won't really get better flow than the stock ones. I'm eventually going to replace it with a Bonez one when it starts to crap out.

Later.

 

I looked at the catco's too they are cheap. I got the dynomax one they are alot better. They also garunty they will hold up to the high temps on out cars . I got a pic if anyone wants to see it. Hell it took a month for them to custom make it 2.5 in and 2.5 out its called a super cat 3way 18 inch part number is WLK-15142 $119.00 from summit

 

OK, I am a little confused.

Did you have to get it custom made to fit, thus costing more than $119 total, or is the summit part number WLK-15142 really a custom fit replacement for $119 total?

 

The problem isn't just the heat, it's the hard sharp exhaust pulses. A cheap cat might last for a short time on your TII, but will fail in days on the N/A.

 

But will it hurt the engine???

 

I say custom made cause thats what they called it. LOL it took a month to get . I checked into this with dynomax and they warranty it . it comes 18 inches long and it is made of the exact same thing as the 400.00 ones . just have to get the brackets welded on .

 

Well, a cheap cat will only hurt your engine if it disintegrates and becomes a plugged up cat. If you have a Turbo its pretty easy to see a cat start to plug up, because you start losing boost pressure, but on an N/A you may not know until its advanced enough to have done damage to your engine.

Not sure where everyone comes up with these types of statements except from the adds for the more expensive catalytic converters. I know a lot of near stock N/A and T2 owners that have used the cheap Catco cats for years without having them plug up, down here in Florida. Do a search on this site and check how many people use them, you'll find a lot that have used them for years, including N/A owners.

Like I said before they fail emissions and have to be replaced after two years, and one guy I know in Orlando with a street ported engine actually burned a hole all the way through the center of his within a year , but I have yet to see one "plug up."

Later,

 

High-flow Catco cats are actually pretty good. Supergoat had one on his '88 GXL and had nothing but good things to say about it. Combined with gutted pre-cats, it was a nice setup. Sounded damn good, too.