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Upgrading My Cat

SiR_RB

By SiR_RB,
in Engines & Forced Induction

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SiR_RB Grand Master

SiR_RB

Posted
Posted

hi

ive been doing abit of research, and it seems like 100cell hi flow cats are the way to go if your running more then average power (300kwatw)

i know there are tons on ebay, but the quality is unknown, ive enquired about the CES 100cell 3" hiflow cat they have on offer and im waiting to hear back about flow/warrenty/etc, has anyone got/used a CES cat before ? how did you find them?

also looked at afew catco metal cat ones from justjap but they are 200cell. how much power can you make with a 200cell 3" cat before you need to upgrade? is there reallllyy that much of a power differnce between a 200cell and 100cell ?

i just want to do it once do it right, dont want to keep changing cats becuase they collapse after afew months, or find they are restricting flow

any helpful information would be good !

thanks

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R31Nismoid Grand Master

R31Nismoid

Posted
Posted

300rwkw = 4" cat at least.

I cannot see a 3" honeycomb cat flowing enough. I can feel a minor different with my 4" CATCO cat with a 3.5" exhaust/280rwkw.

It's not major, but its noticeable none the less.

I'd be going with a big 4.5" CAT personally having doing it again.

SiR_RB Grand Master

SiR_RB

Posted
  • Author
Posted

My front pipes merge into 3" collector and my cat back is also 3", can an exhaust place modify a 3.5" or 4" cat down to 3" flanges? That way the internals are huge and flow more ut will fit my system perfect ?

Cheers

saliya Rising Star

saliya

Posted
Posted
hi

ive been doing abit of research, and it seems like 100cell hi flow cats are the way to go if your running more then average power (300kwatw)

Less cells = less surface area for catalyzing = bigger holes. More flow at the expense of less effective catalyzing. At some point the conversion will stop being legal.

I have a metalcat cat (6" body, no idea what the in/outlets are supposed to be but probably 3.5"). I would guess it's 200cell as I don't think they had 100cell then.

For what it's worth it's been under the car for a few years, been through many track days and a couple of intercooler-pipe-blew-off

fireballs that destroyed the car's glasspacked mufflers.

I recently pulled it off the car and while a little black, it seems to be in perfect working order. Can't ask for more than that.

Cheers,

Saliya

SiR_RB Grand Master

SiR_RB

Posted
  • Author
Posted
Less cells = less surface area for catalyzing = bigger holes. More flow at the expense of less effective catalyzing. At some point the conversion will stop being legal.

I have a metalcat cat (6" body, no idea what the in/outlets are supposed to be but probably 3.5"). I would guess it's 200cell as I don't think they had 100cell then.

For what it's worth it's been under the car for a few years, been through many track days and a couple of intercooler-pipe-blew-off

fireballs that destroyed the car's glasspacked mufflers.

I recently pulled it off the car and while a little black, it seems to be in perfect working order. Can't ask for more than that.

Cheers,

Saliya

what sort of power are you making with the 200cell metalcat?

GTScotT Grand Master

GTScotT

Posted
Posted

As usual I see lots of confusion on cat sizes.

Most people take "5" cat" as having 5" flanges, me included. Where as people are refering to the actual body of the cat. It could have 2" flanges for all we know.

The body is also important, the larger the body the larger the cell size at a given count. A 5" body with a 200 cell count will flow worse than a 4" body with a 100 cell count etc.

I think people in the know need to be more specific when stating figures with cats.

saliya Rising Star

saliya

Posted
Posted
what sort of power are you making with the 200cell metalcat?

1 power run @350rwkw before the dyno overheated.

I intend to visit another dyno with a slightly-different setup sometime soon (same cat / similar exhaust).

Will remeasure and repost.

Cheers,

SW

scotty nm35 Grand Master

scotty nm35

Posted
Posted
I've got a Xforce "highflow" cat, and i just found out they are 500cpsi... shit!

anyone used one of the ones floating around ebay?

http://cgi.ebay.com.au/ws/eBayISAPI.dll?Vi...e=STRK:MEWAX:IT

Yep, i have bought 2 now. Mine is flowing great, not sure about the emissions though. I cut the inlet back to make it 3.5 inch.

post-63525-1285751322_thumb.jpg

scotty nm35 Grand Master

scotty nm35

Posted
Posted
should probably make sure it's emissions legal, otherwise you may as well run a decat ;)

They apparently meet euro3 standards, what else can you go by? Stops the smarter cops shoving something up there and finding the hollow pipe I guess.

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