Shifter Linkage Upgrade Options

[Montreal914]

When I first saw the JWest shift linkage upgrade (NLA), I though it was a very elegant way to handle the support of the ball sleeve mechanism in the side shift gearbox console. I assume cost was the reason Porsche didn't do it that way.

I've always wanted to do something similar (IMG:style_emoticons/default/stirthepot.gif) . Being on a budget, I decided to modify/fabricated all of the components myself but pretty much all of this upgrade can be done with parts available through our member vendors here in one form or another.

Here we go! (IMG:style_emoticons/default/sawzall-smiley.gif) (IMG:style_emoticons/default/smash.gif) (IMG:style_emoticons/default/welder.gif) (IMG:style_emoticons/default/driving.gif)


Shift Console Preparation

All of this started when I got a spare gearbox with a broken shift console. I though this was the perfect candidate to play with since it can't be used in its current form. I cut the remaining part of the bushing tab and file the casting flush.





Then I prepared what would be the two new supporting tabs in which there would be oil impregnated bronze bushings. These tabs are made from a 1 1/4" x 3/8" aluminum flat bar. The 7/8" hole was machined in the right location (center 15mm from the console reference surface) to maintain the stock position of the shift rod.





The bronze bushings (McMaster Carr 6338K426) were grooved to accept a snap ring (McMaster Carr 98585A115) to secure them to the tabs.




Using a piece of 5/8" shaft, I do the first layout of the assembly.




Then, with a file (aluminum is a beautiful material), I did the weld preparation of the various surfaces as per recommendations from my welder.








Then my welder did his magic while taking his time and extra care to make sure the material didn't pull which would have resulted with bent tabs where bushings wouldn't have lined up and ruined the whole thing. Yes the preferred way of doing this would have been to weld first and machine after but that would have made the machining of the tabs more expensive due to an elaborate setup to hold the console. I would probably do it this way if I was doing it again, but since I had a good welder, he pulled it off nicely (IMG:style_emoticons/default/sunglasses.gif)






Then I used my trusted hack saw and files to smooth it out and bring it to a shape that could ressemble somewhat a stock casting form. (IMG:style_emoticons/default/w00t.gif)






Last, I reassembled the rest of the components with a fresh seal and the console assembly was ready to be installed on the gearbox. (IMG:style_emoticons/default/beer3.gif)

[Montreal914]

Next step was to start working on the front rod of the shift linkage, the one hidden in the tunnel.

My plan was to use two steering shaft U-joint which requires 4 spline stub shafts to connect to each side of both joint. So two joints and two shaft were needed for this project.

Front shift Rod Modification

The first thing I did was to take some measurement on the car to make sure I was keeping the same overall geometry. Then I drilled the four plug welds that are holding the rod end that connects to the stock joint by the firewall in the engine bay.




I ended up cutting the tube leaving four little tabs for the new rod end installation.




Then I cut the first steering shaft to get the splined end that would go at the end of the shift rod.







Measure twice for proper location. You can see where the four tabs were pinched a little to close the little gap between the tube ID and the steering shaft OD.




Welding...




File the welds and sand smooth. Verification of the new 20mm firewall spherical bushing fit. That completes the preparation of the front shifter rod. (IMG:style_emoticons/default/beer3.gif)