cats after mufflers
Thread Starter
Intermediate
Joined: Jun 2007
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From: plympton mass
cats after mufflers
I was wondering if anybody ever put hi flow cats on after the mufflers because of no room. I have long tube headers and corsa exhaust the only place i have room for hi flow cats is after the muffler but i never heard of anybody doing it or if is legal . any input helpful
Last edited by vett40; Apr 25, 2011 at 07:47 PM.
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That wasn't his point. The lack of heat issue far outweighs the location issue (unless you're in front of a judge that is! 
) Once you're past the belly of the car, cats are basically worthless. (This is straight from Magnaflow too.)
Cats work only when enough heat is present to activate the catalyst operation. If there's not enough room behind the headers, you won't be able to run them. (Remember there's some very small-bodied cats.)
FWIW, I modified the best header configuration for my use (long secondary 4-2-1 headers) just so there'd be room for cats. Look at setups that offer bolt-on cats as an option. See how they do it.
) Once you're past the belly of the car, cats are basically worthless. (This is straight from Magnaflow too.)Cats work only when enough heat is present to activate the catalyst operation. If there's not enough room behind the headers, you won't be able to run them. (Remember there's some very small-bodied cats.)
FWIW, I modified the best header configuration for my use (long secondary 4-2-1 headers) just so there'd be room for cats. Look at setups that offer bolt-on cats as an option. See how they do it.
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Thread Starter
Intermediate
Joined: Jun 2007
Posts: 35
Likes: 0
From: plympton mass
thank you for the input guys . i was trying to do two things with the cats. In mass 96 and under don,t have emisions test but they are suppose to visually look for cats. the second thing was trying to make it a little quieter. thinking now about short racing mufflers
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From: Toronto ontario
There is room after the headers install hogh flow cats that are the bullet style. Magnaflow and random tech makes cats that are fairly short and cut the corsa piping where they 'Y' close together after the bellhousing and install them there. There is lots of room up front everyone else has them right behind the headers.
