Bill,
While I'm no expert on the subject either, I think the answer is in the vane
design. There is only pressure on one side of the 'pump'. The induction
vanes are shaped somewhat like the agitator in a washing machine. The
incoming gas stream comes in down the middle and is thrown to the outside
where the port to the intake manifold is. For gasses to go back out the
carburettor would be like something trying to go down in a hurricane vortex.
If you remember the old "tilt-a-whirl' amusement park rides where you are
pressed to the walls of a rotating cylinder and then the floor drops away,
could you imagine trying to pry yourself off the wall and moving toward the
center of the cylinder? Just in case my explanation is off base, I'm
cc'ing this to the list where more turbo-knowledgeable minds will set us
both straight if needed. And of course, the knowledge-less will post about
how much noise a cat makes when its tail gets caught in a turbo. Gee, I
sort of wonder about the answer to that one myself.
Regards,
Glen Byrns
'59 bugeye
'59 Morris Traveller (Winifred)
>
> What I still don't understand (bear with me) is the case where the car
> is running at say 3K RPM, and the throttle is 1/2 open. I would think
> that the pressure in the manifold from the turbo would go into the
> cylinders when the intake valves opened. I would also think that it
> would go out the carb throat since the throttle is 1/2 provide a path
> for the compressed air travel. I believe that that is not the case but
> I don't understand why.
>
> Bill Gilroy
>
> PS. I didn't ride the short bus to school :-)
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