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A Lil Somethin Somethin About Cat Converters

seraphyn_r33

By seraphyn_r33,
in Engines & Forced Induction

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seraphyn_r33 Proficient

seraphyn_r33

Posted
Posted

Hey guys,

Got my PowerFc installed and tuned about 3 weeks ago, and am very happy with it! makes my r33 fun again! haha

ALTHOUGH ive noticed over the last week or so, my car has started to knock to pretty high levels on occasion. So since i will have to drive back to get my car re tuned, or at least have a closer look at the ignition maps (3 hour drive to melbourne) i figured i will replace my cat converter. My car has a turbo back JJR exhaust, and yes my exhaust has an infamous x force hi flow cat. i figured i may as well anyway, will most likely gain kws and car maybe run a little better. i think anyway? haha

Are the x force cats really that bad??? could it even be one of the factors to why my car may be knocking sometimes??? (car has the following mods - turbo back exhaust, FMIC, Fuel pump, Power FC, makes 200 rwkws) or just the tune?

Which brings me onto my main question, where can i find supply of "metalcat" cat converters?? ive tried psi products twice, and also emailed them and received no word back, the only other supplier i found was justsr.com, but the phone number on the site rang out. I want one in a hurry, as i will need it on my car by about next weekend

Question number 2 is, is there any other brands of cat that are of equal quality??? any experiences?

and question 3, it seems quite a few people on here have said that their metalcats are collapsing??? so should i maybe steer clear of them now???

i know there is a few threads on this, which i have read. but any more info would be very very much appreciated

Cheers

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

knocking will be more to do with the tune id imagine... cell or two needing adjustment

To test just drop the cat, replace with a pipe and go for a drive.

You'll soon see if you know how to get the knocking going under certain conditions

Wogan Proficient

Wogan

Posted
Posted

i don't know a lot about cats, but the $160 Xforce one i got from just jap isn't very good. It's causing an exhaust flow restriction at high rpm and i'm losinga decent chunk of power.

also looking for a better alternative myself. Don't really want to hollow out the Xforce, but it definately would make it high-flowing.

Angus Smart Grand Master

Angus Smart

Posted
Posted (edited)

is the x force cat round or ovalish?

the stainless round ones are fine and are used on many many high horse power cars with no problems at all. the others are just a normal ceramic cat

you'll probably find that all of the metal cats use the same core.

Edited by Angus Smart
seraphyn_r33 Proficient

seraphyn_r33

Posted
  • Author
Posted

yeah your right r31nismoid, i figured that more or less it was the tune causing the problem, although im thinking that maybe the cat might have a little to do with it, but like you said, after some runs with the cat and without it, i will soon find out.

a few hours after i wrote this thread, i ended up getting a phone call back from psi, for a 3 inch metalcat it will cost me 280 including delivery from brisbane to albury via australia post, which was a lot cheaper than i thought they would be!

so sleepr85 you have a metalcat on your car, have you had any troubles with it???

SLEEPR85 Proficient

SLEEPR85

Posted
Posted

No problem at all. From what i can tell its as free flowing as i've had. Not tried xforce but have only heard bad things about them on these forums which led me to buy the metalcat. Looks really well made as well so i didn't mind paying a bit extra for something that was gonna potentially improve response and performance.

Angus Smart Grand Master

Angus Smart

Posted
Posted
Not tried xforce but have only heard bad things about them on these forums which led me to buy the metalcat.

the problem with xforce is, people think this is a high flow cat

xfhighflowcat.jpg

when realistically its just as cheap and ceramic as any other cat on the market.. around (160) and is perfect for emmisions etc.

i figure most people are using this type as it comes with xforce exhaust systems.

now for real high flowing cats with a metallic core.

xfmetalcat.jpg

this is an xforce item and these are very good! my friend installs them all the time, and never had any problems what so ever on alot of very high hp cars!

HEKT1K Grand Master

HEKT1K

Posted
Posted
the problem with xforce is, people think this is a high flow cat

xfhighflowcat.jpg

http://www.skylinesaustralia.com/forums/Fo...gh-t161580.html

well with threads like the above on our own site, do you blame them? they are advertised as high-flow.... perhaps they shouldn't be? i've been looking at getting one of these, but judging by people's comments now im thinking twice about it.

Angus Smart Grand Master

Angus Smart

Posted
Posted (edited)
http://www.skylinesaustralia.com/forums/Fo...gh-t161580.html

well with threads like the above on our own site, do you blame them? they are advertised as high-flow.... perhaps they shouldn't be? i've been looking at getting one of these, but judging by people's comments now im thinking twice about it.

i'd say they will be alot more high flow than the standard 15 year old cat still on your import when it comes in :dry:

a problem with skylines and most imports, they run a bit rich on the standard computers and this will clog up a cat in no time!

your better off going with a cat around the $300 mark aka a cat with a metallic core.

Edited by Angus Smart

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