down a GT350 Mustang
to download this
about 6.5 Mb, MPEG format)
Chris Streit in his '70 RSR-bodied 911
short video clip illustrates a mis-shift resulted
in significant engine damage. Due to the remote
location of the shift housing, 911s are more
susceptible to a missed shift than other vehicles.
helps prevent this from occuring.
mpeg clip is approximately 30 seconds long. About
26 seconds into the video, listen for the
split-second mis-shift from 3rd into 2nd (instead
of 4th). Although this event happens quickly in
this highly stressful environment, it was just
enough to damage the engine.
courtesy Chris Streit)
was pushing very hard at Road America exiting The
Carousel corner #9 at the top of 3rd gear,
approaching 100 MPH. This year I switched to the
GTO class where the average car has 2-3 times the
horsepower of my 911 so I have to hustle. The
G-forces in this turn force the driver hard to the
left side of the car.
I attempted the 3-4 shift I pulled the selector at
a slight angle unknowingly into 2nd gear. As you
can see in the video, the clutch was only out for a
few 10ths of a second, but it was enough to force
the engine well past redline."
damage pics (click for larger images)
end result was 6 well-bent exhaust valves, a
shortened weekend, cracked valve guides and
required a full teardown to repair and re-measure
Gate Shift kit installed in Chris Streit's
track car (click
"I have since installed the
915 Gate Shift Kit
insurance against this problem.
was clear that the design would discourage this
sort of accidental motion with the lever
re-centering, and the detents on 1-2. I also
received an added benefit. I discovered that it
really made for a more intuitive shift pattern
through the gears, as 915's tend to be a bit loose.
My shifts are much more smooth and I spend a lot
less time worrying about what gear the lever is
going into. The kit made me more comfortable with
my 3-2 shifts because the added lever guide gives
the shift a more "positive" feel.
I am very satisfied not only with the mechanical
benefits , but also that my mind is able to be off
my shifting and back onto the track!
for a great kit!"