Does a blow off valve have to be mounted straight up and down? Or can it be mounted at 90 degrees? The truck is going under the knife shortly and I am trying to get all the answers I need before I tear into her. Any help would be appreciated. Thanks

Brett

 

You should be able to mount a BOV in any orientation that you choose. The spring keeps it closed until there is enough engine vacuum to open it and expel the excess intake pressure. The BOV does not rely on orientation for it's operation.

 

I asked some similar questions a few weeks back and got some good replies here:

https://www.performancetrucks.net/fo...d.php?t=355210

From all the pics and answers I got, and from sufing the net it does not seem to matter.

 

I had to mount mine straight down, heres why. I have a TIAL BOV and originally mounted it straight up. It sits about 6" upstream of my MAF sensor and after the IC on an STS setup. It seemed evry few months my engine would start bucking and jerking. I kept finding water on my MAF. After a lot of trial and error I discovered that the BOV was building condensation and it was seeping into the intake tube. I pulled the BOV apart and it was full of water. I turned it facing down and have never had the problem again.

The pic is what it looked like when I had the problem. You can see it behind my SS oil return line. I just loosened the clamps and rotated it 90 deg.