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Old 08-30-2007, 10:38 PM   #1
slugish
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Join Date: Jan 2005
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Question Performance Gain By Removing Cat.

iHAVE A 408 CI. SMALL BLOCK IN MY 84. ITS PROBABLY AROUND 375- 400 HP. BASED ON WHATS BEEN DONE TO IT. iHAVE HEDMAN HEADERS GOING TO 3 IN. COLLECTERS GOING INTO 1 PERFORMANCE (CATCO, i think) converter. then a single 3 in. pipe going to a single flowmaster .with 2 2 1/4 pipes out the back . question : would I gain anything by :
*1 removing the cat.

*2 running a true dual system


#3 or getting a flowmaster (if they make them) with dual inlets & dual outlets , no cat . would this not act as a x pipe of sorts .
Iread some where that even the perf. cats are pretty restrictive . Any ideas appreciated
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Old 08-31-2007, 12:19 PM   #2
bufmatmuslepants
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Re: Performance Gain By Removing Cat.

flowmaster mufflers dont flow very much better than OEM. a strait through muffler like a bullet one or magnaflow moves air much better. when i deleted my cat on my camaro i felt a TINY difference, but when i did on my truck i felt nothing, probably because the truck is so much heavier and that small amount of power is not noticable. your setup with the 3" I pipe is like the one i have on my camaro, cept i have no cat. its LT headers, 3" collectors into 3" Y into a 3" I pipe, then single magnaflow with dual 2.5" outlets. ditching the cat and picking up a higher flowing muffler is probably the cheapest way you can do it, although nothing beats true duals for performance and sound.

or you can do a cutout right before the cat and have no resistance when you want it
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Old 08-31-2007, 03:26 PM   #3
Captkaos
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Re: Performance Gain By Removing Cat.

You won't gain any if it is going through a performance cat. A 3" single is equivalent in flow to dual 2.5" You biggest gain would be from deficit from your bank account.
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