915 Porsche tranny install complete

["at88mph" <at88mph@xxxx>]

Welp today, after 2 months, the Porsche 915 5 speed tranny is complete and
installed into my DeLorean mounted to the Chevy Vortec 4.3. For those
interested in a similar swap I have to admit, it was quite a bit harder than
the engine swap. On a scale of 1 to 10 (10 being the hardest) I'd rate the
trans swap at a 7. The hardest part BY FAR was engineering the shifter to
work properly. The total on the swap was under $2k and roughly $500 of that
was because my car was a automatic originally and I had to get some DeLorean
parts (i.e. the pedals/master and slave cylinder; however I ended up not
using the stock slave cylinder)

With the engine swap, I didn't do anything that couldn't be reversed so that
the stock engine could be put back in one day if I wanted to. (however
after the first drive in the car with the new engine I realized that I won't
go back to the stock motor) With the 915 tranny though, some fabricating
involved cutting SOME of the frame to mount the shifter and also for the
u-joint that attaches to the front of the Porsche transmission so I can't go
back with the stock auto tranny without re-welding in a plate to mount the
stock shifter again. (But, as with the engine swap, I won't be going back to
the stock auto) The Porsche unit is a VERY nice and smooth gearbox.

TRANSMISSION:

For those interested, here's how the swap went. I found a Porsche 915
transmission for a REALLY good price on one of the Porsche message boards.
It was out of a '72 model and is perfect because it has no computer
controls...its just a 5 speed gearbox. Its also widely available and parts
aren't expensive for the 915. The trans fits very well into the DeLorean
frame and mounts up PERFECTLY to the stock DMC half shafts with no
modifications! I had to have a custom transmission mount fabbed up. It
incorporates the stock DMC mounts (where they bolt to the DMC frame) and
also the Porsche trans mount. I also had to get the 915 shifter housing and
shift rod.


BELLHOUSING/STARTER/CLUTCH

I found out that some Porsche owners do V8 engine swaps and that a lot of
kit car owners use Porsche/VW transmissions to mount up V8's to. I found a
place called Kennedy Engineering that makes bellhousings for all kinds of
Porsche/VW swaps. http://www.kennedyeng.com/ They had EXACTLY what I
needed; a Porsche to Chevy bellhousing. I also bought a stock Porsche 915
clutch setup and ring gear from them. I'm also using the stock 915 starter.
There are also other places that make these bellhousing kits but Kennedy was
VERY helpful and they were a lot cheaper than the other places as well.
Their customer service is EXCELLENT and their pieces are VERY high quality.


SHIFT ROD/HOUSING:

The 915 shifter housing sits PERFECTLY into the frame of the DMC like it was
meant to be there! The Porsche is a very simple setup b/c they just pretty
much have a straight shift rod that goes from the shifter to the tranny. (no
cables or anything, just a straight rod) I had to cut the 915 shift rod
because it was MUCH too long for the DMC frame. On the DMC though, there is
a down angle, of course, from where the DMC shifter goes back to the tranny.
This is where the major pain came into effect. Long story short, it was a
very simple fix, we had to weld a swivel in the middle of the shift rod so
that it would give me a down angle for it. That stumped me for a while and
thinking back, it was really simple but hindsight is always 20/20.

HYDRAULICS:

The 915 tranny is actually a 'pull type' setup and is mechanical, not
hydraulic. However, the clutch fork rod (what the cable would have pulled)
sits on a spline and the fork can be taken off and moved in very small
incraments. If you could see the Porsche 915 tranny in a Porsche, the
clutch fork rod would be on the driver's side....what I did was remove the
rod and (since its splined) I turned it around so its now on the passenger
side which now turns it into a 'push type' setup instead of a pull setup. I
then purchased a stock DMC master cylinder and I went to the parts store to
look thru their slave cylinders. I found a slave that was the same size as
the DMC master cylinder to get a 1 to 1 ratio. I then fabed up a bar to
mount it to the tranny and ran a bendable brake line from the master to the
slave. (this part was very simple and only took about 4 hours total to make
and assemble) It worked perfectly. Now I have a very durable tranny that
is cheap to repair or replace mounted to an engine that is dependable and
cheap to fix as well. Also the fact that I now have 5 speeds instead of a 3
speed auto. I'm very pleased with it so far, but it has only been complete
for one day but I'm hoping that I'll be just as happy with it in 6 months
from now and even longer. I was/am very happy with the engine swap and
hopefully the tranny swap will be as enjoyable.


Take care,

Duke