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Re: Bypass valve effectiveness?
Hi all:
Graydon D. Stuckey wrote:
> If I shift gears without lifting my foot off the accelerator,
>will that allow the turbo to keep spinning while I shift gears?
....
....
> Thoughts? Rebuttals? Is there another reason for the bypass
>valve?
The valve is really a safety valve as opposed to a performance item,
to help prevent stalling the compressor, as well as prevent the
pressure spike in the intake manifold when the TB is rapidly closed.
In the Audis I have seen, the compressor does not have much of a
tendencey to stall, (although I imagine there is a pressure spike) but
in my other car, (87 Grand National) the compressor will stall even
with moderately slow closing of the TB. Once I heard this happen in
this car, I ran and got a blow off valve. Stalling the compressor
wheel is _very_ violent, and something no one wants to hear. (once in
a while I hear of a compressor shearing off in these cars, what a
mess!)
BTW, my 5ktq has never made a noise like that, and I'm sure a bypass
valve would be a good idea to add, but it is low on my list of things
to do...
Kevin Ford