Hi flow cat for EK4

[VT1-R]

HI ppl.

I am looking for a Hi flow cat/ Hi flow metal cat to match my Xforce catback n headers. So can other brands of cats bolt on to my current system or mus i get the Xforce brand cat as well. I heard of Magna flow cat, Xforce cat. But i make several mistakes on performance mods along the way. So if i can i wish to get the better cats to match my system.

Also, will i get better flow and a lil bit more of throttle response from a gd hi flow cat. And get even a lil bit more from a hi flow metal cat. So basically, why get a metal cat that cost more? Power gain justify the extra $100 to get the metal cat???

Also, if any1 has a used gd condition one for sale can also pm me. Preferably direct bolt on to Xforce catback n headers.

Tried search but no real concrete info. Cheers ppl.

[nd55]

Hey,

> So basically, why get a metal cat that cost more?

Summary: no need.

Cat converters generate heat in the process of chemically changing unburned hydrocarbons (fuel), carbon monoxide and nitrogen oxides into CO2, water and N2 (I think).

The exhaust is a little bit hotter after it flows through the cat. The cat itself gets hot from the hot exhaust flowing through and the chemical reaction.

Metal cats use a metallic substrate for the precious metal active layer (platinum/palladium/rhodium + more).

The metal substrate is supposed to be structurally stronger than the ceramic used in OEM cats.

OEM cat converters are tuned to have the minimal internal thermal mass, because they need to heat up to operating temperature quickly to pass emissions regulations.

This minimal construction means it can be possible to melt a cat converter down in a hi-po application.

Hence, a manufacturer might use a metal cat for a bit more reliability in a high performance turbo application where there are richer mixtures and more heat involved without installing a a larger cat which takes longer to warm up.

For aftermarket applications with typical header & intake stay OEM. Use a larger OEM from wreckers if you really want too. Just make sure its not clogged.

There's much more to cat converters.
two stage (really old design).
three stage + air injection (old design, not many applications)
three stage (this is why we drive cars tuned to stoichemical A/f ratios and not
lean burn designs).

OBDI, OBDII. newer cats have emissions requirements which mean cats have to convert a larger percentage of pollutants.

http://honda-tech.com/zerothread?id=1323923&page=1
http://randomtechnology.com/technical.html

[Kiz_EG6]

HI ppl.

I am looking for a Hi flow cat/ Hi flow metal cat to match my Xforce catback n headers. So can other brands of cats bolt on to my current system or mus i get the Xforce brand cat as well. I heard of Magna flow cat, Xforce cat. But i make several mistakes on performance mods along the way. So if i can i wish to get the better cats to match my system.

Also, will i get better flow and a lil bit more of throttle response from a gd hi flow cat. And get even a lil bit more from a hi flow metal cat. So basically, why get a metal cat that cost more? Power gain justify the extra $100 to get the metal cat???

Also, if any1 has a used gd condition one for sale can also pm me. Preferably direct bolt on to Xforce catback n headers.

Tried search but no real concrete info. Cheers ppl.

Hey man, 1st of all the advantages of a metal cat is mainly just the durability.
If you are pumping out 800hp, then you will blow the shit out of anything less!!

Basically, any can will fit up to your existing exhust, it is just a matter of flanging both the header and the cat back correctly!

I would probably go a 2.25 or 2.5 inch cat but no bigger or smaller if you want to maximise power!

[dsp26]

actually if your not going to get a metal cat may as well keep the factory metal one.

ceramic ones get murdered by exhaust pop especially if it happens a lot

Here:
http://www.ozhonda.com/forum/showthread.php?t=80166

[VT1-R]

thanks for quick replies.

So i should just get a Hi-flow cat(normal one) to maximise power.

Or should i get OEM cats from other honda cars that are more free flowing.

Surely, a hi-flow cat will not make mi lose power? So 2.25 inch gd?

[Kiz_EG6]

actually if your not going to get a metal cat may as well keep the factory metal one.

ceramic ones get murdered by exhaust pop especially if it happens a lot

Here:
http://www.ozhonda.com/forum/showthread.php?t=80166

...and how often do you think this happens on a stock engine?!?
A basic hi flow cat is definately worth doing, as i said, so long as you are not putting down 800hp!!

[dsp26]

...and how often do you think this happens on a stock engine?!?
A basic hi flow cat is definately worth doing, as i said, so long as you are not putting down 800hp!!

lol.. ok... changing any part of the exhaust system will increase exhaust pop if you haven't noticed, especially on straight through systems.... oh and it always happens when you back off throttle....

the purpose of the cat is to ignite/burn uncombusted gasses...

but your right it rarely happens on a STOCK engine thats backpressured which he doesn't have

and any additional power that a cat can provide doesn't have much to do with size but rather the surface area of the catalyst, because an efficiency of a cat is also graded by how hot it can get.... efficiently burning the uncombusted gasses that pass through increase the scavenging effect of the exhaust system as it again accelerates gas flow out the exhaust... uncombusted gasses cool down the exhaust and slow down flow and reduce vacuum.

[Kiz_EG6]

lol.. ok... changing any part of the exhaust system will increase exhaust pop if you haven't noticed, especially on straight through systems.... oh and it always happens when you back off throttle....

the purpose of the cat is to ignite/burn uncombusted gasses...

but your right it rarely happens on a STOCK engine thats backpressured which he doesn't have

and any additional power that a cat can provide doesn't have much to do with size but rather the surface area of the catalyst, because an efficiency of a cat is also graded by how hot it can get.... efficiently burning the uncombusted gasses that pass through increase the scavenging effect of the exhaust system as it again accelerates gas flow out the exhaust... uncombusted gasses cool down the exhaust and slow down flow and reduce vacuum.


I read the link you posted, if thatn is the price you got on a metal cat then i would have to agree with you, just some of the prices i've seen are ridiculous.
Also i've never had a problem with my standard hi flow and that was with 4:1 extractors and a 2.25" cat back, it popped a bit, but you sorta had to try to make it do it!!

[dsp26]

yep they are good prices and shipped within 5 business days.
only disadvantage of purchasing such design of CAT as opposed to oval ones is it loses sound deadening properties.



and yep i'll be honest and i'll say it here only, I do not agree with 99% of performance prices here in australia when I know I can get CHEAP, QUALITY, DURABLE, PROVEN, PERFORMANCE items in the USA with careful selection and research.

those combination of words are rarely found together and never at all here in Australia. Not that i don't support our economy or 'performance scene' but wtf.. it's non existent, a lot of parts sold by shops are sourced overseas anyway and sold for jacked up prices despite getting bulk discounts.

[/rant] + *flame suit NOT on and NOT needed*

[VT1-R]

so bottom line to my question. Just get a basic xforce hi flow cat?