Re: popoff valves

[Glen Powell <gpowell@acacianet.com>]

I don't think so.

WG = exhaust gas bypass valve for the turbine side of the turbo, vents
excess exhaust to the exhaust system (on street cars) downstream of the
turbine when boost pressure reaches a preset threshold -- threshold can be
computer controlled, totally 100% mechanical (Ur-Q) or pneumatic or
combinations of all of the above -- pretty sure a lot of the Ur-Q Pro-Rally
cars and Quattro RR cars vented the WG exhaust directly to the atmosphere
through an additional WG exhaust pipe -- big flames and sounds!!

pop-off valve = relief valve for excess boost pressure on the output of the
compressor side of the turbo/intake manifold/throttle-body that vents the
excess boost to the atmosphere -- more big noises!

'turbo bypass valve' = the same as the pop-off valve, but, it vents the
excess boost back into the compressor inlet, creating a closed-loop system -
quiet

All can limit maximum boost but in different ways and at diferent times. No
combinations are mutually exclusive.

>Subject: popoff valves                                                         
>isn't a popoff valve and a wastegate the same thing?                           
>frank                                                                          

"Extremism in the defense of liberty is no vice and moderation in the
pursuit of justice is no virtue."

Vorsprung durch Technik,

-glen