I am building my throttle body for my N/A 20b, a 3 1/2" monster!  for
aviation use, what is really needed?  Are springs really necessary to keep
it closed or open?  it seems to me that the throttle cable takes care of
that.  perhaps a small spring to hold it open in the case of a broken cable?
I realize I will need an adjustable stop to control how much the valve
closes.  some have holes drilled in the butterfly so it never totally shuts
off the air flow.  is this needed?
    because I am attempting to reuse some 20b carb parts it is possible I
may have some minor air leakage thru the butterfly axle.  it is sliced in
the middle to accept the butterfly but a bit too long and the sliced portion
may extend past the bearings.  I can plug that up or have it welded, but
then I wonder what difference this makes if the valve needs to be kept
partially open at idle anyways?
Kevin Lane  Portland, OR
e-mail-> n3773@attbi.com
web-> http://home.attbi.com/~n3773
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