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Delete the cats or run a cutout?

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Old May 7, 2008 | 10:37 AM
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Default Delete the cats or run a cutout?

Need advice on either deleting my highflow cats (just putting a straight pipe in their place) or leaving them in and just running a 3" cutout. I have the Magnaflow catback (3" I pipe with 3.5" tips), LTs and making 392/362 currently. I'm trying to squeeze out every bit of power I can in order to hit 11s. I've heard talk of loosing back pressure with no cats and loosing TQ but gaining HP. No concerns on the emmisions issues or being too loud but I deff don't want to loose too much TQ.

What would you do in my case?

Thanks
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Old May 7, 2008 | 10:45 AM
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It would be easier to delete them.....
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Old May 7, 2008 | 10:57 AM
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Originally Posted by Carshopinc.com
It would be easier to delete them.....
Do you know if they make a prefabbed pipe to take the place of the cat or do I need to just make one? The only problem I see is creating the flange because my car uses the round type clamps on both ends of the cats so the header collector and the cat pipe flange sandwich together.
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Old May 7, 2008 | 11:18 AM
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are you running manifolds still? Or headers and if so which ones?
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Old May 7, 2008 | 11:30 AM
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Not sure what kind of headers due to them being on the car when I purchased it. I know this is a problem so I guess the muffler shop weld in would be my only option?
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Old May 7, 2008 | 11:35 AM
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I vote delete them...having cats AND cutouts kind of just multiplies the things that can go wrong. its hard for a straight pipe to go wrong.. lol. plus you can maybe get a little cash for the hi-flo cats...don't know if they'd pay out as well as stock ones, might not even be worth crap
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Old May 7, 2008 | 11:38 AM
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Originally Posted by jmmullin
I vote delete them...having cats AND cutouts kind of just multiplies the things that can go wrong. its hard for a straight pipe to go wrong.. lol. plus you can maybe get a little cash for the hi-flo cats...don't know if they'd pay out as well as stock ones, might not even be worth crap
jmmullin, what type rwhp gains have you seen when deleting the cats?
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Old May 7, 2008 | 11:56 AM
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I can't delete mine I live in NC and have to pass a visual emissions test. I just got some $35 "hi-flow" ones off ebay and stuck em up there behind headers then ran them to an xpipe, magnaflows, and dumped before the axle. I can't see you gaining more than 5-10 rwhp off a catless system over one with cats. Nothing your pants will feel upon acceleration.

I've also heard taking cats off makes the car sound more raspy, and I'd rather it be deep, muffled and just alow rumble at idle. My car idles really low, but if you stand anywhere near it you feel vibration in the ground and the air from the dumps. Just hinting at the power

we've got pretty similar setups, minus my heads and FAST 92... what is your car putting down right now? I have yet to take mine to a dyno for a tune...

EDIT: D'oh. nevermind. see it in the sig lol
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