catalytic converters and mufflers

Hey guys on the focus what do you suggest for catalytic converters and mufflers.

I want it as quiet as I can get it but not squelch the flow.

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TSSFAB.US No HYPE just parts!!!! And check us out on Facebook!!!

I am really happy with the magnaflow on my Volvo. Flow master's are way too loud. Add a $50 spun metal cat at the end of the system, should be OK.

Man I hate that cat rule. It is just stupid. By positioning the cat at the end of the system isn't it useless? Not enough heat to function?

I am kind of surprised to hear you(Sean) say that. Why not a bung on the cat in the stock location?

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Zap zap my ass...

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slidewayswrx
Man I hate that cat rule. It is just stupid. By positioning the cat at the end of the system isn't it useless? Not enough heat to function?

I am kind of surprised to hear you(Sean) say that. Why not a bung on the cat in the stock location?

Not that it really applies to many here.. but I think the SCCA rallyx rules for M2 and M4 say you need at least one cat and it can't be any further back in the system than the last factory cat was.

I doubt anyone would really get dinged on it and I live in CA so my cat issues are well.. issues..

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This isn't floor mat anarchy

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slidewayswrx
Man I hate that cat rule. It is just stupid. By positioning the cat at the end of the system isn't it useless? Not enough heat to function?

I am kind of surprised to hear you(Sean) say that. Why not a bung on the cat in the stock location?

FWIW, cats back there work.

I got my rally car past our emissions testing, with zero changes to the exhaust, or ECU mapping.

Car runs a "100 cell" metal cat about 6" in from the tailpipe. No other mufflers or reasonators.


Cats do not like 2 things:
1. Heat
2. gravel blasting.

A cat under the car in the OEM ish location won't last long at all... the heat from running WOT so long, and the gravel blast that gets thrown at them. They will come apart.

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Chris

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Car runs a "100 cell" metal cat about 6" in from the tailpipe.

Sadness. This would never fly in CA, even if it did pass the tailpipe test (which if mine does now, it still should).

The heat/gravel pounding are 1/2 the reason I'm building a 'race exhaust' so my stock stuff can sit until I need to go get smogged again. I don't mind killing a few race cats here and there, but replacing CA legal cats puts a hurting on the budget.

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This isn't floor mat anarchy

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Do It Sidewayz
FWIW, cats back there work.

I got my rally car past our emissions testing, with zero changes to the exhaust, or ECU mapping.

Car runs a "100 cell" metal cat about 6" in from the tailpipe. No other mufflers or reasonators.

I also run a cheap cat back there. Aside from the 5' chicano having trouble reaching the pedals or braking and locking rear wheels stalling the car it passes Colorado emissions as well. Or did. Future rally cars are going to be Wyoming based to avoid this nonsense.

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Grant Hughes

I like the magnaflow on my street car just fine. It is of the "see straight through it" lack of restriction variety, and I don't think it's too loud. I might thinnk otherwise if it didn't have a snail to quiet it down as well, but that's just me. rallycar just has a cat at the back, again to keep it outta the rocks, and it works as well.

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Jay Woodward
Snohomish, WA
'90 Mazdog Frankenprotege
Chronologically, 46...

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SteelSolutions
Hey guys on the focus what do you suggest for catalytic converters...

Uh, run NASA so you don't have to have one? *grin*

I know, I know, geographically that's a bad fit. I'll let other folks continue with the mechanical suggestions.

Anders

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Grassroots rally. It's what I think about.

Pat, I am not a fan, but easy to change there, and passes the rule. They do work that far back. Bonus is after hammering on the car, it glows orange inside, visible from behind the car. Looks really cool at night!

Chris forgot to mention he's running on E85, surely that makes a difference when it comes to emissions...

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MRWmotorsports
Chris forgot to mention he's running on E85, surely that makes a difference when it comes to emissions...

True...but pretty sure we could get it past on gas too.

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Chris

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alosix

Not that it really applies to many here.. but I think the SCCA rallyx rules for M2 and M4 say you need at least one cat and it can't be any further back in the system than the last factory cat was.

Prepared, not Modified.

And yes, it is completely stupid, because they instated that rule because "these are theoretically street cars" but meanwhile engine control electronics may be reprogrammed or piggybacked, which has the potential to be WAY more heinous emissions-wise than the removal of the cats.

I can't wait for the first person to have functioning antilag (the old pyrotechnic kind) on a Prepared class car. It's legal if done within those limitations, after all. And they don't say what KIND of catalyst must be used, or any definition of what a catalyst is, just that it must be no more than 6 inches further back than the rearmost OE cat... so you could legally take, say, a 3" cheapo cat, run a 2 7/8" holesaw through the middle, sleeve it with a pipe, and it's still legal.

By the way - don't tell anyone I said that.

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Pete Remner
Cleveland, Ohio

1984 RX-7 (rallycross thing)
1978
Silence is golden, but duct tape is silver.



Edited 1 time(s). Last edit at 03/09/2012 08:47PM by Pete.

Oh.. Evil

I'm swapping back to a stock turbo, which will make me prepared legal (if I install the trim/carpet. but I still have it). Just one reflash to a group N derived rom I have good 'fire out the tailpipe' anti-lag and launch control.

You guys are making me want to just stick one on the rear of the car. Wonder if the CA po po would bug me in transit for Mendocino and Gorman...

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This isn't floor mat anarchy

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Pete

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alosix

Not that it really applies to many here.. but I think the SCCA rallyx rules for M2 and M4 say you need at least one cat and it can't be any further back in the system than the last factory cat was.

Prepared, not Modified.

And yes, it is completely stupid, because they instated that rule because "these are theoretically street cars" but meanwhile engine control electronics may be reprogrammed or piggybacked, which has the potential to be WAY more heinous emissions-wise than the removal of the cats.

I can't wait for the first person to have functioning antilag (the old pyrotechnic kind) on a Prepared class car. It's legal if done within those limitations, after all. And they don't say what KIND of catalyst must be used, or any definition of what a catalyst is, just that it must be no more than 6 inches further back than the rearmost OE cat... so you could legally take, say, a 3" cheapo cat, run a 2 7/8" holesaw through the middle, sleeve it with a pipe, and it's still legal.

By the way - don't tell anyone I said that.

How loose is the rule? Does the cat need to be in the flow of the exhaust or could you just mount it to the floor of the car inside the cabin as long as it was not more than 6" from the original position?