Evac. Valve ?

[MO RAPTOR 700]

I think I know the answer to the ?, but I just want to be sure.

The valve is to be installed to let the air out of the crankcase but not to let any air be drawn in correct?

This will let the piston on the down stroke push air out and the piston on the upstroke will draw a vacuum.

Thanks

[Colorado700R]

that's correct tony

[MO RAPTOR 700]

that's correct tony

Thanks Aaron.   

[Magz]

what are the benifits and where can i get one?

[MO RAPTOR 700]

what are the benifits and where can i get one?

Benefits are better rings sealing and a small gain in HP=.5-1.5HP so I've read.
I got mine from Racers Edge in Arizona and is name is Jason.

[wobble]

My buddy did a back to back dyno with and without the evac valve.

[Krandall]

holy crap.

that's unreal!!!! 4hp @ one 6250rpms!!!!