Removing BOV

[Jon Olds]

Thanks. I am still struggling a bit with the concept that not dumping a reasonable volume of compressed air has a minimal affect on throttle response. Is the compressor that efficient it can refill the empty plenum in the time it takes the driver to open the butterflies again? Or is it the mass of air that has to restart moving again after the butterflies open again?
Think my rally car bov is going to be dumped. My gt30 running a 34mm inlet restrictor has way too much lag.
Anything that helps (with spending more dosh changing the A/R) has to be worth a go
Jon

 

[Makaveli_se7en]

The only thing that worries me is does the compressor stall, or has it got enough enertia to make it through?
Jon

This is a common misunderstanding of the word "Stall" perpetuated by the aftermarket BOV manufacturers.

Stall in this case is aerodynamic i.e. flow separating from the compressor blades similar to a plane that tries to climb too sharply and has nothing to do with speed of rotation.

 

[PobodY]

So the compressor essentially looses (aerodynamic) efficiency when the back-pressure is too high? However as soon as the throttle is open again, and the air flowing, it regains it? - Is that a bit like a form of self-regulating; the turbo is still spinning, but not pushing anything?

 

[campbellju]

In practical terms when running 1.8Bar on a 3017, With a BOV, manifold pressure dropped to 0 as soon as you lifted off the throttle to change gear, without a BOV the inlet manifold pressure dropped quickly at first but in a typical gear change would still have 0.7bar of pressure by the time you are re-applying the throttle. So the intake had a 0.7Bar advantage when pressurising again.

 

[Jon Olds]

Bring it on. That must reduce lag noticeably, my meagre brain says

 

[PobodY]

I think this will prove to be another one of those things where technically dumping the air improves the life of turbo and/or throttle bodies, but in reality it's not significant; especially on a car that's already modified. - That's the impression I've got from Ed's input anyway.