Exhaust 88 318 with lt headers
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From: Camp lejeune North carolina
Exhaust 88 318 with lt headers
I just got new lt headers on my 318 which is still out side of the truck.. I was just wondering what diamiter exhaust would go good on her.. I heard 2" because of back pressure... Im doing H pipe with glass packs
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From: Pittsburgh, PA
I think you'll find this discussion is a lot like buttholes. Everybody has one. Area of a circle is pi*radius*radius. So for a single 3" pipe, its 3.14*1.5*1.5=7.065 square inches. For two 2" pipes, its 3.14*1*1*2 pipes = 6.28 square inches. For two 2.5 inch pipes, its 3.14*1.25*1.25*2 pipes = 9.8125 square inches. One 2.5 inch pipe would be half of that, which is 4.90625 square inches.
This should just give you an idea of how much room your exhaust has to flow through. Velocity and friction and crap will also change. As you can see, dual 2" pipes should flow similar to a single 3" pipe. Dual 2.5s can move a lot of air.
Then there is always the question of whether or not there is such a thing as too little backpressure, especially when you have an h-pipe to scavenge your exhaust and keep the velocity up.
This should just give you an idea of how much room your exhaust has to flow through. Velocity and friction and crap will also change. As you can see, dual 2" pipes should flow similar to a single 3" pipe. Dual 2.5s can move a lot of air.
Then there is always the question of whether or not there is such a thing as too little backpressure, especially when you have an h-pipe to scavenge your exhaust and keep the velocity up.
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From: Camp lejeune North carolina
Well im going for deepest sound with glass packs.. Just dont know what is "too little" back pressure is... Im leaning toward 2 1/4 just right in the middle...