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Posted by: Mike1981 Oct 22 2014, 06:44 AM

Hello

I have been following this thread closely and saving my pennies to buy one of these adjusters

My 914 has a tailshift 901 tranny and I just read this will not work on a tailshift

Is there a similar tool one can buy to help with the adjustment of the shifter?

The P.O. replaced all the bushings but I'm dealing with a renegade with a custom linkage

Tranny shifts fine but finding the gears is still a problem.

Im told trying to adjust without experience may lead to making matters worse

Any help on this?

Thanks

Mike

Posted by: Racer Chris Oct 22 2014, 07:26 AM

The side shift is the more common setup, and one which people are often encouraged to update their early cars with, due to the quirks of the tailshift setup.
As far as I know, I'm the first to create a marketable solution for the sideshifter so I highly doubt you'll find anything for the tailshifter.

Posted by: Dr Evil Oct 22 2014, 08:22 PM

The tail shifter has a lot of slop in all of its internal shifter components, at the very least. Consider this, the stock 911 that uses the 901 has one internal slop point. The 914 adds two more points directly in line with that first one. So, while some work can be done to fairly easily remove the fore/aft slop (I have a solution in the works for this), the side to side is still pretty shitty. With a tail shifter I do what I call "quadrant shifting"; first is somewhere in this quadrant, 2nd in this one, etc.

A side shifter is a fairly cheap investment and can lend itself to some major improvements over the tail shifter. I have a nice improvement that is simple and makes the side shifter more gated than stock, so improvements for that system are available over the inherent improvement over the tail shift.

Posted by: r_towle Oct 22 2014, 08:29 PM

Take a look at the rear of the tail shifter linkage and see how much slop you have there....sometimes that metal piece gets worn and some welding and grinding to decrease the tolerance can help.

Another place to clean up is the shifter itself has a bushing in it, and old tired springs.
Rebuilding that shifter also helps remove slop.

There is a cup bushing down at the bottom of that shifter, replace that.

It's not an unworkable system, and in reality, once you adjust either of these shifters properly, you are done adjusting...there really is one good place for your car...find it and leave it alone.

My first pass at these cars I did everything I could do with that tailshifter linkage, shifter etc.
I rebuilt the tranny also...

Finally swapped in a side shifter.

Posted by: cpavlenko Oct 22 2014, 09:53 PM

Soooooo, what's needed to go from tail to side shifter.

Posted by: Racer Chris Oct 23 2014, 04:59 AM

Transmission, complete linkage and engine crossbar.
And a new firewall bushing.

Posted by: rhodyguy Oct 23 2014, 06:59 AM

+NEW inboard mounts, the correct bolts for and the late brackets for the late bar, and the solid outboard bar mounting pieces. to really complete the package, the correct warm air guide for the drivers side. another overlooked item in the tail shift trans is the rolled pin inside of the rear of the tail shifters. they can fail. a vague shift pattern, that seems to change can indicate a bad pin. some used shifters can be better than others. the plastic cover for the rear rod console is a nice piece to have too.

Posted by: dknechtly Oct 23 2014, 07:17 AM

First step is to replace all the plastic bushings, balls and cups. This alone will gve a vast improvement. If there is a lot of side-to-side slop in the very back (where the linkage couples to the tranny), I've had good luck putting a homemade shim between the metal ball of the linkage and the shift lever. I made mine of house heat/air ducting type metal. Make it big enough with some tabs so you can kind of wrap it around to stay put.

Posted by: Mike1981 Oct 23 2014, 07:19 AM

Thanks for everyones advice

I think I will try to look for a cable shifter for my 901

Any designs out there that have worked well?

Posted by: DBCooper Oct 23 2014, 07:49 AM

Ouch. Plus labor, so not simple, and definitely not cheap. And you're discarding the tailshift transmission, since no one wants them. Almost no one.

It's not really cheap, Doc, but what exactly does "major improvement" mean? I don't know many people who are that pleased with the way their side shifter shifts. Witness the products, the Rennshifter, metal bushings and bearings, Chris' side-shift mechanism, his new adjuster, etc., all expensive and evidence that even people with sideshifters are still trying to find some way to get them to shift better. So maybe "improved" over a tailshifter, but still SLAP.

A cable shift for tailshifters would definitely be the way to go, should make a tailshifter work as well as or better than a sideshift transmission. Would probably be a cheaper and more effective solution for improving sideshift transmissions too, but unfortunately no one's come up with a really good one yet. Sorry Brandwood, nice try, no cigar.

Posted by: mepstein Oct 23 2014, 08:29 AM

Replace all 5 plastic bushings. adjust, enjoy. It's a 40 year old car. Appreciate for what it is.

Posted by: Mike1981 Oct 24 2014, 02:40 PM

Yes I agree

The P.Ol swapped out the bushings

I need to get the nerve to adjust the shifter

Or bail on it and go to a cable shifter

Mike

Posted by: Hank914 Oct 24 2014, 05:33 PM

I just moved from a tail to a side, and I am pleased. I could have just done the bushings and lived with the tail shifter, but since I was rebuilding anyway, I thought I'd get as much improvement as I could. I don't have the Renn or the metal bushing, but the improvement over what I had and what I now have is night and day.

Posted by: Dr Evil Oct 24 2014, 06:01 PM

A cable shifter for a tail shift is folley. You still have the very large slop points in the transmission itself.The shift linkage external to the tail shifter is not all that bad, and is actually superior in some parts if all in tolerance.

Side shifter conversion is cheap because the external parts to convert can usually be had for about $100-125. The transmission itself is not all that expensive, depending on your location. Sunny = cheaper. Salt belt = more $$.

Some will never be happy until they have a gated shifter feel. I base my comment on the 100+ satisfied people that I have personally helped, that have been very happy with the change, and that feel it is absolutely worth it. As for cheap improvement, my side shift internal modification is working very well, has been tried by one independent evaluator and they were surprised and happy, and will not cost all that much when I have completed beta testing. Now that I am done with the move to my new shop, I only need to get set up to complete the R/D. I am shooting for $100.

Posted by: Cap'n Krusty Oct 24 2014, 06:45 PM

Careful attention to detail when setting up a side shifter tranny and linkage, coupled with good driving skills and development of proper shifting technique nearly always results in outstanding shifting performance. You wanna speed shift across the natural pattern and drive it like a sloppy old beater, it'll return the favor ... But then that requires practice and self discipline, so it's probably not the way to go ...

The Cap'n

Posted by: Dr Evil Oct 24 2014, 07:02 PM

Well stated