Let's talk High Flow Cat

[Supra469]

Which one do you have how do you like it.

Also, for those of you using test pipes chime in also.


To ensure I continually pass my emissions I have to have a cat installed.


Would like your pros/cons size brand & price and pic would be a bonus! Thanks.

 

[mkIIIman089]

I bought (and will again possibly) Random Tech. It looked good, can't comment on its performance.

 

[hellraiser456]

i got my cats removed with a full custom DP.....and well...i would never put them back in....we don't have any strict emissions here so they would never check.

 

[IJ.]

Using a 3.5" MetalCat here and while it's not too bad flow wise if you overheat it it does punch the internal matrix back a bit

 

[figgie]

had a Random Tech 3" metal substrate cat. Worked like a champ.

You know that brings up another point. Everyone always says the cats, whether aftermarket or OEM are restrictive yet have to see ANY single dynos posted to prove that fact.

 

[swaq]

I bought a universal 3" Vibrant from Horsepower Freaks. I haven't installed it yet, I'm a lazy bum...

 

[dbsupra90]

had a Random Tech 3" metal substrate cat. Worked like a champ.

You know that brings up another point. Everyone always says the cats, whether aftermarket or OEM are restrictive yet have to see ANY single dynos posted to prove that fact.

i gained 115rwhp when i took off the cat. oh wait, i upgraded the turbo at the same time so maybe that isnt a fair comparison.

seriously tho, i have a mag article here where they did a hi flow cat shootout. they flow tested several different oem and aftermarket cats, as well as straight pipe. if anyone cares, i'll see if i can find it and post the numbers. if i recall, the random cat was the best. i believe it flowed <5% less than straight pipe.

but, i have yet to see dyno comparisons.

 

[JustAnotherVictim]

What's a cat?? :biglaugh:
I was actually curious about this as well.

 

[lagged]

there is no such thing as a "high flow" cat. the only thing you can do to improve the flow is to get a cat with a larger ID.

 

[7Mboost]

move to FL and don't worry about or temporarily shove some steel wool in there lol.

 

[BorHor]

I ran gutted cat for a while and hated it. Ended up getting another cat.

 

[figgie]

My happy ass is going to be laughing when all of a sudden Florida does bring back emissions (for you young tikes emissions was taken off from Florida in the early 90's).

Why would florida do that you ask?

Well they are running out of options to make money

 

[SevenMKIII]

Then move to IL :biglaugh: no emissions here. My car's not drivable yet so I can't offer my opinions on a cat. I didn't have one on my last three cars!

-Chris

 

[Supra469]

For those that do have a cat, whether your car is runing or not, don't forget to list the brand and price (if you remember it) lol.

 

[starscream5000]

I have a 3" Cooleeze testpipe with the built in hangers for the stock mounting locations. I've heard many people complain about the hangers not fitting, but I've had no problems, it fit like a glove. One stipulation I do have though is that any cooleeze flange, be it on a test pipe or downpipe, is shaped a little differently than the standard 3" flange found on most test pipes, DP's, and catbacks, but they seal fine. I also wish Greg would have included crush gaskets instead of the paper ones.

 

[isnms]

My high flow 3" cat is the Exhaust Depot from Supra Store. $180.
It even has the flange for the wideband sensor
http://supra.stores.yahoo.net/higflowcat3d.html

 

[figgie]

Keep in mind

that Cats can have two material inside

the ceramic substrate one which is more dense. Or the metal substrate one which is higher flowing. The Random Tech Cat I have IS CARB legal (have to look the number up at home).

P.S it is also for sale as I ahve a 4 inch one now

 

[MRSUPRA]

I was running an RT high flow CAT for a while. I switched to an equal size test pipe and my boost jumped from 18 to 20psi with no other changes. That alone tells me that the RT CAT was restricting flow. I will never go back to catolitic converter unless its Emissions time..

 

[Blade2001]

I am running 3" RT cat.. never passed emissions ever since!!! may be it has to do with 550s and Lexus AFM..

 

[figgie]

I am running 3" RT cat.. never passed emissions ever since!!! may be it has to do with 550s and Lexus AFM..

psst

cats have to be in the stioch range for them to be effective. And actually, optimally it has to be going from stoich or close to to lean and back and forth. This way the cat can actually do its work.