Supra Forums banner

Aftermarket BOVs on stock MAF sensors

994 Views 4 Replies 3 Participants Last post by  mervinnn
How the fuck do you make them work!? :)

I don't get it, I have had a Blitz SS BOV in my basement for almost 2 years because I couldn't get it to work right! The damn thing would bleed air during boosting and also cause a crappy idle if I ever revved the car in neutral, basically the car would almost stall then come back to normal idle. I tried tightening the spring with the nut but basically It ended up being so tight the BOV never opened at all thus making it useless.

I don't understand the concept of the Blitz SS BOV, it seems to simply be a spring loaded valve. How is the BOV supposed to hold air in during boosting but then expel air during abrupt deceleration? How does it differentiate? What exactly does the hose coming off of the top of the BOV do?

Who ever gives me a good answer can have a used 6 speed Supra shift knob I have! :) I'll even pay shipping.
1 - 5 of 5 Posts
The BOV is forced to stay shut by the boost in the hose going to the nipple on the BOV. That boost pressure, accompanied by the spring pressure, keeps the valve closed during boost. When you let off the gas, the intake manifold goes into vacuum, thus producing vacuum in the line going to the BOV nipple. This vacuum overrides the spring pressure in the BOV spring, and opens the valve, releasing pressure from the intake piping.

Comprende?? :)
I remeber looking in my old blitz catalog seeing that it comes stock with a spring that holds 16psi of pressure. If you're running higher then that that would explain the leaks under pressure. They do make an upgraded spring that allows the BOV to hold 21 psi. Generally that is high enough for most users. This could be the root of most of your problems.
Thanks for the replys dudes.
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.