sequential gearboxes

[G. Scott Ponton]

    Well I guess I will have to put my foot in my mouth on this one :-) I
have been shifting a 4 speed without "lifting" for over 25 years. It's a
little hard on the syncros in some boxes but isn't that hard to accomplish.
It's just a matter of timing the shift with clutch and shifter. When the
timing is perfect it's unusual for the RPMs to climb more than a couple of
hundred between shifts.
    It's true that there is a need to unload the shift "dogs" in a normal
trans. Although it's not become they are back cut. It has more to do with
the surface area of the dogs. If you grind every other dog off of the gear
you don't have to use the clutch at all. This was fairly commom practice in
the 60's. They used to call them "crash boxes" Worked well until the tires
and power levels got a lot better. Then strength became a factor. For awhile
Perfection-Hi Test made special replacement shift syncro hubs and gears,
which had larger dogs much like a motorcycle trans, for the muncie trans. Do
to the liminted surface area they were prone to junmping out of gear on
de-.accell as the detents weren't stiff enough.
    If you look closely at a motorcycle trans the dogs square without a back
angle. These transmissions are held in the selected gears but fairly stout
detents and notches in the sequential "barrel". Also due to being designed
for sequential operation the surface area of the dogs is nearly equal to
that of a stock automotive transmission.
    There also used to be a company which made sequential shifters for
automotive 4 speeds. I haven't seen one advertised in over 20 years though.
It worked much like a "V-gate" other than you didn't need to lift the handle
to shift down from 3rd to 2cd. you just rowed the shifter handle back and
forth to upshift and after you were in 4th the next time you moved the
shifter you would go the other way. It never caught on, probably because you
had to shift through all the gears every time you wanted to "find" a
particular one.
    As the only thing you need to do is release the pressure on the gear set
to dis-engage the current gear it should be possible to cut one or two
ignition pulses in a NA app. Designing a shifter shouldn't be to hard to do.
You could use air, hydraulic, or even electric. With the proper cam and
ratchet design it would even be possible to upshift and downshift without
having to go all the way to 4th before you could start downshift or all the
way to 1st before upshifting.
    Just my $.02

Scott