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2.5" into 3" cat

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2.5" into 3" cat

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Old

Nov 24, 2004 | 07:32 PM

#1

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Staging Lane

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2.5" into 3" cat

Guys quick question, I have a 2.5" collector on the bottom of my S&P headers, but I have a set of 3" SLP Catalytic converters that I have yet to put on. First question, can I somehow make this work? and Two.. Will it effect performance in anyway?

Thanks,
Clay

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Nov 24, 2004 | 07:50 PM

#2

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I would take it to an exhaust shop and have them to 3" the whole way. Also, I dont think you can do that at home. My exhaust shop did 3" into the 3" cat, then 2.5" out of it. They expanded one end of the 2.5" pipe so it fit in the 3' cat.

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Nov 24, 2004 | 08:35 PM

#3

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You can buy flowmaster reducer cones 2.5 to 3 inch. Nice smooth transitions and works great.

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Nov 24, 2004 | 11:47 PM

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Staging Lane

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Roger that, thanks guys!! I will look into both of them

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Nov 25, 2004 | 01:23 PM

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Trans Am WS6 RGS

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Works fine for me! Im running 3inch cats (Same as you) to 2.5 inch pipes.

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Nov 25, 2004 | 02:01 PM

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I wouldn't do it. It may introduce turbulence into your exhaust system.

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Nov 25, 2004 | 04:14 PM

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Quote:

Originally Posted by Another_User

I wouldn't do it. It may introduce turbulence into your exhaust system.

If done right there will be very little or no turbulence

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