01/19/07 – Starting the
transmission mount
last night's progress...
Cut the rest of the tunnel out
(another 1" from the
rear)1 and
was able to
bolt up the transmission. It fits nicely, there is no need to remove or
even
move the engine to access the transmission bolts... That's a great
feature. Especially
for anyone who has ever tried to change the transmission on a 300ZX2...
I made a temporary transmission mount
out of this prybar 3:
Here are a few shots of the
transmission in the car:
Next, I began planning a transmission
mount. The first step
was to make bolting plates. You can see the two I made here:
The main transmission bolting plate
is made from 7GA Mild
steel. You can see it bolted to the rubber transmission mount. We
decided on
keeping the stock rubber trans mount, despite the fact that we are
using solid
engine mounts. Need to have some compliance somewhere!4
The other bolting plate picks up the
two bolts for the stock
transmission mount. Notice the distance from the rubber trans mount to
the
stock location. Since the transmission utilizes the rubber mount,
simply
joining the rubber mount to the stock location would result in a point
loaded
cantilever beam. The chassis is not meant to maintain such loading
especially
at a point that has already been compromised by tunnel modifications,
so an
alternate solution, or a dual cantilever beam, must be incorporated.
As I mentioned, since so much
material was removed from the
tunnel, a support brace would be desired. This brace was to be located
midway
down the tunnel, underneath the transmission.
Since the forward face of the rubber
mount on the
transmission is about midway back on the tunnel, it was decided that a
transmission mount/chassis brace "subframe" could be constructed.
Bolting plates will be welded to the chassis floor, then the
"subframe" will be bolted to that.
Here is an artist's rendition of the proposed solution:
The transmission mount was fairly easy. It should also provide extra support, as it ties nearly into the main frame rails… It’s currently rusting away in a storage bin at Innovative Tuning…
(1) I think I wound up eventually removing another 2”
(2) The worst transmission job I ever had to do
(3) It’s funny that I took the time to circle it…
(4) I’ve been told that a soft transmission mount coupled with hard (solid) engine mounts gives a fairly vibration free ride… We’ll see I guess…
