Exhaust Size
Thread Starter
|
New User
Joined: Dec 2005
Posts: 22
Likes: 0
From: NJ
Exhaust Size
I just put 5" stacks on my 97 F250. Aside from removing the muffler, the rest of the exhast piping is still stock (including the cat). I am looking into putting in a straight pipe from the bottom of the down pipe to the stacks. Is 5" pipe too large? I had someone tell me that it may be and that you need some back pressure for acceleration. Is this true? If it is, why? I always thought if you open up the exhaust as wide as possible then the motor can breath easier and suck in more fuel/air and you can't go wrong.
FTE Leadership Emeritus
Joined: May 2001
Posts: 13,653
Likes: 6
From: Cabot, Arkansas
The turbo provides all the backpressure your engine needs. In fact, one of the biggest improvements you can make to your exhaust system is to get rid of the stock (squashed flat) downpipe and kitty and go with a nice 3" round pipe. I think I've seen on this board that Tymar offers a DP that is 3" to 5"....should be perfect for your application.
Postmaster
Joined: Apr 2004
Posts: 3,658
Likes: 0
From: Ellensburg, Washington
Backpressure is not important on turbo diesels. The turbo provides all the backpressure that the motor needs. anything after the turbo that creates backpressure will cause turbo lag and this will rob you of power. Straight exhaust after the turbo is best way to go. Large pipe helps to open up the exhaust flow. the smaller the pipe the more backpressure there is. 5" is a great size to go with if your gonna build an exhaust system.
