High flow cat

spetz · Post by **spetz** » Mon Oct 30, 2006 3:35 am

Gonna go buy a high flow cat for the car
At the moment just running a stock Magna/Verada cat

Just wondering, any benefits in spending close to $400 for a stainless mesh cat in an NA motor or should I save money and go a normal ceramic one for much cheaper?

kid_dynamite · Post by **kid_dynamite** » Mon Oct 30, 2006 9:24 am

Are you referring to those MetalCat type ones?

IMO that's overkill for an NA. Yes a high flow cat would be good, but you still need some backpressure and one of those metal-matrix ones are quite free flowing, I'd just get your std hiflow.

FTO338 · Post by **FTO338** » Mon Oct 30, 2006 10:03 am

I agree with dynamite here, there was a test a while ago on one of the maganzine and what they found was, N/A car lose power with straight flow cat then those with a bit of restriction.

bartman · Post by **bartman** » Tue Oct 31, 2006 4:53 pm

does anyone have any prices/contacts

kid_dynamite · Post by **kid_dynamite** » Tue Oct 31, 2006 5:04 pm

I can recommend www.bosimporting.com.au for Catco cats for pretty good prices. He sells both the normal 'highflow' as well as the metal matrix ones so make sure you're getting the correct one. Also need flanges welded on which wouldn't cost more than $50 at your exhaust shop.

khunjeng · Post by **khunjeng** » Tue Oct 31, 2006 8:04 pm

yeah for NA just get a decent one...not super special. I have a 730CFM hiflo in my "other car" not quite the 800 from the CATCO but I dont really care...it seems great anyway.

FTO338 · Post by **FTO338** » Tue Oct 31, 2006 8:14 pm

kid_dynamite wrote:I can recommend www.bosimporting.com.au for Catco cats for pretty good prices. He sells both the normal 'highflow' as well as the metal matrix ones so make sure you're getting the correct one. Also need flanges welded on which wouldn't cost more than $50 at your exhaust shop.

Yes i would recommend them too, i got like 10 highflow cats off them, one for my FTO, great products. They ship them pretty fast too. No hassle what so ever

Nacho · Post by **Nacho** » Tue Oct 31, 2006 8:34 pm

FTO338 wrote:I agree with dynamite here, there was a test a while ago on one of the maganzine and what they found was, N/A car lose power with straight flow cat then those with a bit of restriction.

Did they say why?

FTO338 · Post by **FTO338** » Tue Oct 31, 2006 9:16 pm

Like kid_dynamite already said, N/A need backpressure to run properly.

khunjeng · Post by **khunjeng** » Tue Oct 31, 2006 9:22 pm

Nacho wrote:
FTO338 wrote:I agree with dynamite here, there was a test a while ago on one of the maganzine and what they found was, N/A car lose power with straight flow cat then those with a bit of restriction.
Did they say why?

just get a good one for a few hundred...not the top of the range..u should be fine.

Post by **Bennoz** » Tue Oct 31, 2006 10:04 pm

Hmmm

I paid almost $550 for a stainless top of the line cat. When I picked it off the shelf & looked through it, there was almost no restriction & you know what kind of power I pull out of a non mivec. I'd have to day, if you've got the coin go for it.... it made a HUGE difference to my performance (coupled with complete exhaust upgrade.)

I was under the impression that the majority of back pressure is created by the general size of the exhaust. Ie not going bigger than 2.5 inch suits the FTO well. Also very much dependent on your compression ratio - for instance the best size exhaust fitted to my mini was 3.25 inch coupled with 12.5:1 compression.

spetz · Post by **spetz** » Tue Oct 31, 2006 10:05 pm

Looking at that catco 3" small body
Is that ok or do I need the large body one?

Also, I have 2.5" exhaust mandrel bent, should I get 2.5" or 3" cat?

Post by **Bennoz** » Tue Oct 31, 2006 10:10 pm

spetz wrote:Looking at that catco 3" small body
Is that ok or do I need the large body one?

Also, I have 2.5" exhaust mandrel bent, should I get 2.5" or 3" cat?

Match it to your system. If you got 2.5" then your cat should be 2.5"

khunjeng · Post by **khunjeng** » Tue Oct 31, 2006 11:57 pm

yeah cos the cat does nothing but convert the bad stuff into bettertuff..its not there for flow thats for sure...many ppl remove them all together..

I looked at the stock CAT when it came off...and compareed to the new hi-flo..the difference is amazing...same goes with the muffler.

I just checked my FTO one...its a 500 cfm rated one for a 2.5" setup...I also have a hi-flo muffler..i.e. no direct baffels...I dynoed those together when it was on and I got about 7rwkw gain ..I paid about 400 fitted for the cat alone.

I think I paid about 650 fitted for my new ones on my soap box.

so there u go...

spetz · Post by **spetz** » Wed Nov 01, 2006 2:58 am

I emailed that place and I can have either
2.5" hi flow ceramic of $160
2.5" metal cat for $240

So the difference is only $80 which means nothing to me and at the moment I want what will give me the best gain.
So, more flow, or more backpressure?

Also, I think the cat changes the exhaust sound and I think a metal one will make it sound raspy

bigpitty1 · Post by **bigpitty1** » Wed Nov 01, 2006 10:35 pm

I got mine fitted for $200, in performance gain I reacon it feels like the same gain that I got when I fitted my extactors to my stock exhaust but with the new exhaust fitted.

After I had it fitted my car has developed a crackle in the exhaust note from 4000rpm and up, sounds tough now.

spetz · Post by **spetz** » Sat Nov 04, 2006 4:57 pm

Which one did you go for bigpitty?

Does anyone know which one I should go for?
Ceramic high flow or steel high flow?

payaya · Post by **payaya** » Sat Nov 04, 2006 7:06 pm

Bennoz wrote:Hmmm

I paid almost $550 for a stainless top of the line cat. When I picked it off the shelf & looked through it, there was almost no restriction & you know what kind of power I pull out of a non mivec. I'd have to day, if you've got the coin go for it.... it made a HUGE difference to my performance (coupled with complete exhaust upgrade.)

I was under the impression that the majority of back pressure is created by the general size of the exhaust. Ie not going bigger than 2.5 inch suits the FTO well. Also very much dependent on your compression ratio - for instance the best size exhaust fitted to my mini was 3.25 inch coupled with 12.5:1 compression.

Size of exhaust depends on size of motor. No way the Mini runs such a big exhaust unless its forced fed.

Post by **Supplanter** » Sat Nov 04, 2006 7:39 pm

payaya wrote:
Bennoz wrote:Hmmm

I paid almost $550 for a stainless top of the line cat. When I picked it off the shelf & looked through it, there was almost no restriction & you know what kind of power I pull out of a non mivec. I'd have to day, if you've got the coin go for it.... it made a HUGE difference to my performance (coupled with complete exhaust upgrade.)

I was under the impression that the majority of back pressure is created by the general size of the exhaust. Ie not going bigger than 2.5 inch suits the FTO well. Also very much dependent on your compression ratio - for instance the best size exhaust fitted to my mini was 3.25 inch coupled with 12.5:1 compression.
Size of exhaust depends on size of motor. No way the Mini runs such a big exhaust unless its forced fed.

If memory serves me correctly it is a $60k supercharged Mini