MORE backpressure

[climberfreak]

okay so i built this exhaust and i lost so much back pressure and low end torque as a result . . . so my question is some exhaust designs have a fin design inside for back pressure correct? anyone have any other ideas of what i can add to create backpressure?

 

[Trill]

http://www.nightrider.com/biketech/exhaust.htm

 

[dave_xb12r]

I would try adding some mesh inside. something like this. Maybe two layers an inch apart.

 

[climberfreak]

just on the inner walls? or like a tube shaped form?

 

[climberfreak]

nice trill ima give this a shot and see how i like it

 

[climberfreak]

so common sense tells me if i put more than one baffle in my exhaust would i get more back pressure but would this help me with more fine tuning? and how llarge of a washer would i need to use for a 4" muffler

 

[Trill]

i would use a pretty big washer. then all you have to do is change the angle of it to tune where the power will be.. top end or down low.. more backpressure the better. Washer 90degrees (most backpressure) the lowend would be better and with the washer 45degrees and less you would gain more top end.. so the theory says . I'm sure there is more science to it but give it a try.

Put a big azz washer in there and have it at 90degrees and see if your lowend is better. You can always change it later..

Put this washermod a few inches before the outlet..

Make a tunable baffle by purchasing a 1/4"x1" thumb screw or taking a 3/4" outside diameter washer and weld it to the top of a 3/4" x 1/4" bolt. Now Drill a 1/4" hole about 1" from the end of the drag pipes. Take the tunable baffle and place a 1/4" nut and a lock washer (away from the large washer) the on it. Now insert your tunable baffle into the exhaust pipe like the example below.

This is for drag pipes so I'm not totally sure if it would be as helpful but if this doesnt work try putting some of that mesh in the pipe and pack a little fiberglass inthere between the 2 walls of mesh...

Let us know how it goes.

p.s I hope you plan on re-mapping your ecm with such a free flowing exhaust.

 

[climberfreak]

p.s I hope you plan on re-mapping your ecm with such a free flowing exhaust

lol yea i really need to ugh....

 

[RudysSI]

Try the adjustable washer method and let us know how it works, i'll be curious.