Improved S-Knob

[russ southerlin <russell.s.southerlin@ast.lmco.com>]

Paul,
When we spoke on the phone a few months ago I mentioned that I was going
to try putting a check valve inline with the W/G vacuum line to prevent
engine vacuum from being applied to the W/G. 

After thinking about it, when the engine is in a vacuum condition (idle,
part throttle, between shifts), I think there would be the same amout of
vacuum on both sides of the W/G which would give the net effect of only
the mechanical spring keeping the W/G closed. I might be all wet with
this theory!!!

At any rate with the check valve installed I think there is a noticable
difference in how fast the boost pressure comes up during gear shifts. I
have a mechanical boost gauge and can see that the pressure comes right
up to about 6 psi when shifting before it lags for a second or two and
then takes off for 15 psi. Without the check valve the boost only comes
up to about 2 psi before lagging and then taking off to 15 psi. I did
put a small pin hole in the hose to the W/G to prevent any pressure
spikes from gradually building up pressure on the W/G above what is
required for the 15 psi of boost.

I haven't tried any timed runs yet but the throttle response between
shifts does seem a little better by the seat of the pants. 

If anyone is interested in trying it out for themselves I have a source
for the check valves. E-mail me directly. They are small plastic units.
Cost about $5 each plus shipping.

Russ
87 5KTQ