Turbo Lag - Bypass Valve!

[Johnny]

ARTHUR OKUN wrote:
> 
> so you mean  you keep the turbo revving high and vent the unneeded
> compressed air into the atmosphear  with that if done properly you
> wouldnt need a waste gate just a servo controlled bleed valve.
> i think they use something like that on pressurized turbocharged
> piston light aircraft cessna p210, piper malibu and etc.?

They use both. The bypass valve keeps the manifold pressure within specs 
when you let off the throttle, like when you start a descent, and the 
waste gate keeps the turbo speed and boost within specs when you apply 
full throttle for take off at low altitude. Some have a manual waste 
gate that you adjust in the run up before take off so that you are 
getting the desired manifold pressure at full throttle. Some use an 
automatic servo operated waste gate based on differential pressure to 
prevent turbo overspeeding at high altitude.

-j-