what defines a high flow cat

Chris Brown · **Posted:** Wed Mar 24, 2004 1:54 pm

sts can't uses high flow cats, so what defines a high flow cat?

does the rule book define the specifications? (no i don't have a rule book to go look at, sorry :oops:

).

Wes Eargle · **Joined:** Mon Oct 27, 2003 9:47 am **Posts:** 3683

Chris Brown wrote:

sts can't uses high flow cats, so what defines a high flow cat?

does the rule book define the specifications? (no i don't have a rule book to go look at, sorry :oops:

).

I'm under the impression that you must use stock catalytic converter(s) in their stock location in STS.

Aaron Buckley · **Posted:** Wed Mar 24, 2004 2:16 pm

Wes is correct. There is a lot of talk about this within STS for some aftermarket headers require the movement of the catalytic converter(s) on some cars, which by the rules, is illegal. - AB

Chris Brown · **Posted:** Wed Mar 24, 2004 2:18 pm

Wes Eargle wrote:

I'm under the impression that you must use stock catalytic converter(s) in their stock location in STS.

you could be correct...all i could find online was that sts couldn't use a high flow cat, but i don't know if that means you 'have' to use the stock one.

the reason i ask, is that i want to get a larger diameter downpipe (part of the a header so it's sts legal)...most all downpipes sold for my car come with a new cat, and if they don't then i have to figure out how to mate up the dp with my stock cat. i'd rather find a complete unit and not worry about having to do some creative welding.

Chris Brown · **Posted:** Wed Mar 24, 2004 2:35 pm

ok then, i guess that answers my question. luckily, i won't have to move the cat, i'll just have to figure out how to connect the dp to the cat.

Aaron Buckley · **Posted:** Wed Mar 24, 2004 2:45 pm

Chris Brown wrote:

Wes Eargle wrote:

I'm under the impression that you must use stock catalytic converter(s) in their stock location in STS.

you could be correct...all i could find online was that sts couldn't use a high flow cat, but i don't know if that means you 'have' to use the stock one.

the reason i ask, is that i want to get a larger diameter downpipe (part of the a header so it's sts legal)...most all downpipes sold for my car come with a new cat, and if they don't then i have to figure out how to mate up the dp with my stock cat. i'd rather find a complete unit and not worry about having to do some creative welding.

Be careful how you interpret the rules on this on Chris. From the local level, neither I nor anyone may care, but at the National level it would be a different story. Making sure the location of the cat doesn't move a mm is critical, for on a turboed car, we all know what moving a cat a little downstream and putting a bigger downpipe will do for turbo spooling :eek:

- AB

Tom Hoppe · **Joined:** Wed Aug 20, 2003 10:16 am **Posts:** 387

Just another clarification. STS rules do not state that you cannot use a high flow cat. They state that you cannot modify the stock cat in any way.

-Tom

Wes Eargle · **Joined:** Mon Oct 27, 2003 9:47 am **Posts:** 3683

Tom Hoppe wrote:

Just another clarification. STS rules do not state that you cannot use a high flow cat. They state that you cannot modify the stock cat in any way.

-Tom

If I am interpreting everything that I have read from the SCCA correctly, unless they actually state that you *can* use a high flow cat (as in STX) then you cannot.

Aaron Buckley · **Posted:** Wed Mar 24, 2004 2:56 pm

Once again, I agree with Wes

- AB

Chuck Frank · **Posted:** Wed Mar 24, 2004 3:44 pm

Tom Hoppe wrote:

Just another clarification. STS rules do not state that you cannot use a high flow cat. They state that you cannot modify the stock cat in any way.

-Tom

IMHO Replacing the stock one with a hi-flo one would constitute a MAJOR "modification". :lol:

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