X-Mozilla-Keys:                                                                                 
Jeff Spitzer wrote:

Gaddy, Robert G wrote:

To Marv Kaye,
I was just thinking (sometimes my brain runs without my permission), "what
if you had a table full of various turbochargers, which one would you
choose?".

I suppose that you would consider a turbo that could only make the desired
manifold pressure at sea-level with no waste gate at all at full throttle
(less weight, complexity, etc.).  I suppose this turbo would have a large,
less restrictive to flow (but possibly heavier), exhaust housing.  If
the turbo seized, the restriction to normally aspirated flow would be
minimized, making the most horsepower until you could get home.  If you
got just a little more manifold pressure than desired, a fixed by-pass

could

be made for fine tuning.  I understand Paul Yaw has to provide a by-pass on
the turbo engine he built for George.

You might think, "what's the point, I'm not making much boost?"  This
would be true, but the turbo speed would increase with altitude, carrying
more
(maybe sea level) pressure up to cruise altitude.  I just don't like waste
gates.  I have a turbo truck (diesel) with no waste gate, and don't miss
it. I have a dune buggy with turbo and waste gate, and always have to

"fuss"

with it. I would hate to try to make moving parts survive a 1,700 deg F,
corrosive atmosphere. My general understanding is that the waste gate is
provided to produce power sooner at lower RPMs, not an issue with an
airplane.

This is what I will be trying to do with my installation.  I came up with a
really neat idea for an exhaust manifold last night.  I'll share it when
the solidworks model is done.

Jeff Spitzer

 
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