With all the enhancements available for our shift linkage, there's still one thing no one has ever addressed.
Adjusting the rotation so all three shift planes are where they belong relative to the lever assembly has always been a PITA, and is even more difficult with a Rennshift due to the small opening to access the pinch bolt.
In addition, installing a more precise shift linkage assembly, like we all crave, makes precise adjustment even more critical.

There should be a way to maintain alignment of the tunnel rod with the fork under the shift lever, and make precisely controlled rotation adjustments in a minute or less.
An idea I've had on the back burner for a long time has finally reached the prototyping stage.

I'm going to test a replacement Fork piece (914 424 171 01) machined from billet that incorporates a worm type adjuster against the splines of the tunnel rod.
If it works it I believe it will be a game changer.

Ooooh, that sounds mighty tasty!!!

--DD

I have no idea what part you are referring to but put me on the list for one

Here's a solidworks model to help identify the part I'm referring to.
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I have been mulling this over for years as well, and only recently started collecting stuff to mess with it. Looking forward to seeing what you develop and your data

me too

I should have a "proof of concept" part in hand sometime tomorrow.
If it functions as expected I'll make a full prototype right away.

My original idea centered around an add-on piece that clamped to the rod but I think the current direction is much more elegant and will provide really easy adjustment.

I must say it never cease to amaze me all the great people who continue to invent new ways to improve our already great old cars! Many thanks to you and all the others! Oh Ill be watching for a release date.

Always thinking

That reminds me, I need to get one of those oil pressure kit thingys from you in the near future

I had a Rennshift pop off at an autocross and it was tough getting it back in then tougher to line up. My fingers hurt after trying to get into the tunnel! Should be a good product!

Cool!

Seems like a great idea!

However, couldnt the adjuster go on either end or even in the middle?
Wherever it is cheapest to reproduce the part with the mods I guess.

I am picturing a worm gear like a hose clamp with no slop and a locking screw of course.

So, you really think that you are smarter than the engineers that gave us an unsealed battery sitting over a crucial structural component of the car, yet under a hole that water can enter freely?

You truly believe that your ideas could be better than those that gave us foam in the rear quarter taillight area and trunk lid frame?

Of course those guys probably had two beers at every lunch, so you can't expect them to get everything right.

Looking forward to see how this works out.

Good point...

I've had the benefit of 30 years experience with what they created, and more than a few deep contemplations on the various "mistakes" made by the factory.
So if I actually do make an improvement that doesn't necessarily mean I'm smarter.

Oh, no. Here you are mistaken. Yes it fuching well will! A worm screw to angle the assembly. What could be more elegant? We might say out of kindness that the engineers thought of this and were told it was over budget. Or we might say something else. Well done!

It's possible that 30 years later, the local micro brew industry around your shop is better than the Stuttgart beer was back in the day.

A simple explanation.

If you are interested, I would be more than happy to give you my car to go from meh, to install all you bits for testing and trial....of course I would pay for the stuff....

Great thinking ! Where does this part fit ?

Once again, Chris is going to get more of my money. Love this concept after struggling with adjusting mine for so long.

Damn, you're right about that! I've already been thinking about those cool pushrod tubes!

The first thing I tried didn't work well enough (too delicate) so after a little searching on the internet I found some components which I think can be readily adapted to my concept.
Here's an updated model showing the worm and gear pieces in the assembly.
Support for the worm hasn't been modeled yet.
I intend for the gear to be a light press on the splined shaft so it will act as a fore-aft locator, yet not rotate independently of the shaft - that is if I can successfully broach the id of the acetal gear with a piece of the splined shaft.

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So ready for this item!

add me to the "list"... had that same issue adjusting the rennshift on both my '14's...

I was having trouble envisioning this until this pic. Super cool. Cant wait to see your functioning part

I get it now. So this would compliment all the other upgraded parts by allowing you to precisely adjust the linkage. Nice!

Very nice Chris. Sign me up

David

Def interested

I have always hated adjusting my shift linkage. This would make it really nice! Good work Chris!

First working prototype is ready for trial installation.

The nylon worm has a 3/16" allen socket molded into the top.

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I like this! I just upgraded to side shift, and this is exactly what's needed.

Put me down if the list has started.

Couldn't agree more. Thanks for working on this!!

And I get the general concept of the design, but is the adjustment (in your prototype at least) made with the allen bolt? And if yes, what keeps the shift rod locked into position once the adjustment is made?

That's pretty slick....definitely interested in one of those!

I feel another 914 shirt coming

EDISON

TESLA

FOLEY

Looks great

Im in for one !

Mike

Looks like the bolt vertically through the coupler squeezes the coupler tight against the rod, just like stock piece. So that's what holds the adjustment, and the worm gear can provide fine adjustment after the pinch bolt is loosened.

--DD

I'll take 3.
2 - XL, 1 - LG please

Exactly.
As soon as I install the prototype I'll take pictures to show more clearly how it works.

I am probably missing something, but why are two pairs of holes provided at the base of the shift lever attachment. A bolt is shown in the lower pair of holes. Is this a short shift option?

Looks great Chris.

You are correct sir!

Chris,

Why not go metric instead of 3/16". All of Porsche is metric. Perhaps consider 4,5 or 6mm.

Let's make working on our cars simple. What is simpler than metric?

David

I always look at metric options first, however I won't force the issue if it increases the cost.
Production volume of an item like this doesn't justify an investment in custom made miniature worm gear pieces.
This is what I found available - off the shelf - for a proper test of concept.

Until my order arrived I didn't even know a hex pocket was molded into one end of the worm body.
It simplifies the assembly compared to my original plan.

So far I'm very encouraged by the results.
Although the production component will undoubtedly be noticeably different from the prototype.

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Cant wait to try this out!

Fantastic!

Wow! that is pretty cool!

That's nice work Chris. More accurate and a heck of a lot easier than nudging that thing like 20 bazillion times.

Chris, pardon my engineering ignorance but it looks like this would be a universal part for all 914s, including 914-6s. Is that right?