Boost v BOV

[Cookiemonster]

Alan, you do not need to SET a bov. All you need to ensure is that the BOV does not leak at the boost levels you wish to run.

The difference between the pressure in your intake pipes and the manifold vacuum is what opens the bov.

[Camotec]

i thought the flutter was the wastegate venting to the atmosphere??

[ProZac]

Usually the flutter is turbo reversion, but now your just confusing the matter.

[Will]

Some BOV's are labelled as 'adjustable blow off valves'.

Here's a quote from GFB's site (http://www.gfb.com.au/faq.htm) which explains what their spring tension adjustment is for:

"How do I adjust the spring pressure to suit different boost levels?

You don't need to! At full throttle there is equal boost pressure on both sides of the piston, so it doesn't matter what boost level you are running, the pressure balances itself out. It then requires very little spring pressure to stay shut. The spring adjustment is used to match the VACUUM signal of the car. The idea is to adjust the valve so that the piston remains just closed at idle. This way, when you lift off the pedal, the spring will be neutralized so that the boost is free to push the piston open."

For a recirculating valve, it shouldn't matter if its open at idle, so the above info is referring to valves that vent to atmosphere on air flow meter cars.

[pcuser51]

:D Thankyou tom cookie &will you have explained that well thanks. :D