Backpressure?

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Feb 11, 2006 | 05:54 PM

#16

looneylariat

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Joined: Feb 2005

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Man Cleatus that's a nice looking truck! Those 49's look good under there!

Feb 11, 2006 | 06:10 PM

#17

F6Guy

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Joined: Feb 2006

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kens64 is correct. the goal is zero backpressure. to put it simply Backpressure bad, High velocity good. The balance is in the pipe diameter. If you slow down the velocity you will loose the scavaging effect, speed it up and you increase it. Thats why most people say they loose power by putting straight pipes or bigger dia. pipes, the exaust gas is slowing down as it leaves the motor.

Feb 11, 2006 | 07:57 PM

#18

hunter1988

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Joined: Jun 2005

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so what would you do forbetter gas mileage, I am confused (but thats easily done

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Feb 11, 2006 | 09:08 PM

#19

kens64

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Joined: Jun 2002

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From: Rio Rancho USA

Just do what 351M said in his first post. Free up the exhaust system, retune for the better breathing, and you should get better mileage.

Feb 11, 2006 | 11:45 PM

#20

F6Guy

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on a 4.6 engine if going without a muffler I would go no larger than duel 2.250" pipes or a single 3.5" pipe. And run it at least past the cab. You will probly want a muffler on it after a week anyway.