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Posted by: Bill's Racing 914 May 18 2015, 11:29 AM

I just transitioned my 1970 914 from tail shift to side shift. The dilemma was what to do for the firewall bushing since no one makes the firewall transition bushing anymore.

Bruce stone sold me the set of side shift linkages. With it, I asked him to cut off a 6 inch length of the tail shift linkage that goes in the tunnel. It just happens to slip right over the side shift tunnel link. There is some slippage, but it is tolerable. This six inch sleeve is the rusty tube in the photos.

This allows me to use the same tail shift firewall bushing I already had in place. When I put the side shift linkage in place, all I did was push the sleeve as far back as I could against the knuckle joint and used a sheet metal screw to hold it in place. see photos.

So that all the tail shift tunnel linkages don't start disappearing from people cutting them up, I am certain an equivalent stock tube size is available that will work.

Works like a champ.

Posted by: r_towle May 18 2015, 11:42 AM

smart.

Posted by: screenguy914 May 18 2015, 12:24 PM

That sleeve surface looks pretty rough. Could be an effective way to enlarge the nylon bushing. You don't want that.

I believe Tangerine Racing offers a firewall shift tube bushing.

Sherwood

Posted by: mikedsilva May 18 2015, 01:10 PM

I recently bought the parts to convert my tail shifter, from Bray Mayeur.
He actually welds a tube to the shift rod, in the same spot where you have your tube.. the only difference is that he polishes the tube to a near mirror finish so it is nice and smooth.. a liberal coating of grease will hopefully keep the surface rust away.

I have not started my conversion yet... tell me, did you have to cut away some of the internal bulkhead to stop the rod rubbing when selecting 1st or reverse?

Also, did you buy a complete side shift box, or did you dissect your existing box and swap the selector rods etc etc...
Mike.

Posted by: brant May 18 2015, 01:16 PM

when did the conversion bushing go away?

dang....

calling 914 rubber????
maybe Mark will make us one

Posted by: r_towle May 18 2015, 01:25 PM

no cutting should be required to switch transmissions.

For the tranny itself, you need a side shifter parts tranny at the very least.

You need the shift console, all the rods, the rear cover....there is alot of difference.

Rich

Posted by: SirAndy May 18 2015, 02:41 PM

Posted by: Vysoc May 18 2015, 02:47 PM

I believe Patrick Motorsports makes one, as I have one that will be going in my project. It does require some machining to the shift rod, but is a quality piece of milled aluminum with a swivel bearing type mechanism in the center.

Vysoc

Posted by: Racer Chris May 18 2015, 03:02 PM

My firewall spherical bearing doesn't require any machining of the rod.
IMO, the Patrick bearing is not a great choice: 1) Turning the rod down to less than .750" OD leaves the tubing too thin. 2) The bearing must be removed from the firewall to remove the rod from the tunnel. 3) The firewall has to be modified for the bearing frame to be attached.

Posted by: Vysoc May 18 2015, 03:27 PM

Chris,

Just checked out your solution on your web-site, which will bring up another question, which I think I know the answer. Six conversion will it require a different shift rod as I see you offer two different models?

Thanks,

Vysoc

Posted by: BeatNavy May 18 2015, 04:26 PM

I did the side shift switch on my '72 a few weeks back. I'm very happy with my Tangerine Racing Shift Rod bushing. Especially once I installed it facing the right direction . Shifting is much better!

Posted by: Racer Chris May 18 2015, 06:25 PM

I think the bent rod works ok with a six conversion, but the bends are unnecessary. A straight rod works fine.

Posted by: Mike Bellis May 18 2015, 07:45 PM

In a pinch, 3/4" ID PVC pipe makes a good bushing. Tight fit on the rod and tight fit on the firewall.

Posted by: screenguy914 May 18 2015, 08:24 PM

Agree with Racer Chris. In addition, Patrick's "bushing" uses a spherical bearing that's fine for close tolerance spherical movement (yeah, the rod moves at an angle a bit). However, the hardened bearing ID isn't designed for linear motion. However, heavy grease should help mitigate tube wear.

Sherwood

Posted by: Mikey914 May 19 2015, 09:00 AM

I was tapped by BD stone to look into these and have actually started the process. It's nice to have another option but much easier to just have a "stock" bushing to pop in. These are a little ways out still as I'm finishing up 2 other large projects.

Mark

Posted by: Racer Chris May 19 2015, 09:05 AM

I started making a steel filler ring that converts the firewall opening to use a standard sideshift bushing.

Posted by: Larmo63 May 19 2015, 09:29 AM

With a bit of fabrication, won't Chris's firewall bushing fit the firewall?

I have one in my car and I love it.

Posted by: Racer Chris May 19 2015, 11:09 AM

No fabrication required. It fits early and late chassis firewalls.
The housing also has a groove to hold the sideshift boot.

Posted by: Bill's Racing 914 May 19 2015, 01:36 PM

Bruce Stone and I talked about this as an option too. Basically a big machined aluminum washer that rivets on to the firewall. The OD big enough to accept the rivets, the ID small enough to accept the standard side shift bushing.

But if it comes out at $100 from Tangerine, I can have my own made up (I are a mechanical engneer too)...or I will stick with this sleeve solution which only costs the price of a sheet metal screw since I already had all the tail shift stuff in place including the bushing.

I like simple solutions. They are the most elegant.

I agree that I should have polished the sleeve first.

Posted by: Racer Chris May 19 2015, 02:44 PM

Even simpler than you have imagined, and no where near $100 - closer to $20.
Why would I make a more expensive product so someone could continue using something I prefer to see eliminated? That makes no sense.
My firewall bearing is only $56.95 delivered. It will outlast the stock bushing, while providing better support the whole time. Replacement bearings (no housing) are only $17.50, not much different from the stock bushings.

Posted by: Harpo May 19 2015, 04:20 PM

Chris design if far superior, more robust and simplier

David

Posted by: Bill's Racing 914 Jun 7 2015, 12:11 PM

Here's some more info from a new post: http://www.914world.com/bbs2/index.php?showtopic=257289

Looks like Patrick racing has a solution too. Might be worth a try also. Look at the bottom of the post about his shift rod and the firewall bushings. They take 3/4in dia shift rods.

The only problem is the bolt flanges on these bushings may run into the lip around the firewall hole on the early tail shift chassis.

Here's the one Patrick uses from Speedway motors: http://www.speedwaymotors.com/Firewall-Mount-Steering-Shaft-Bearing-3-4-Inch-Shaft-Size,6845.html

An alternate bushing from Speedway would be:
http://www.speedwaymotors.com/Firewall-Mount-Steering-Shaft-Bearing-3-4-Inch-Shaft-Size,6845.html


Attached image(s)

Posted by: Racer Chris Jun 7 2015, 03:03 PM

The Patrick tunnel rod has a straight drilled hole where the cone screw goes.
Just one of many things I don't like about their shift linkage products.

Posted by: Bill's Racing 914 Jun 7 2015, 07:32 PM

But does that mean the $13 spherical bearing from Speedway with the two hole flange won't work?

Posted by: Racer Chris Jun 8 2015, 07:05 AM

TANSTAAFL

Posted by: BeatNavy Jun 8 2015, 07:11 AM

(I've read Heinlein!)

Chris provides excellent support for his solutions, too.

Posted by: worn Jun 8 2015, 08:26 AM

I would buy from Chris anytime. Except I want to do it myself (Young Frankenstein). I had a '72 and am adding the side shift. So for $8



I did nothing at all to the new shift tube, but I did alter the bearing for lightness and fit - it was 3/4 inch originally. Easy to put the bearing in the lathe and ream it out.



Now if I can finish welding the oil tank for the side and get the motor lifted into place I can try it for real!

Posted by: Steve Jun 8 2015, 09:56 AM

That's my ad in the classified. First off, I would recommend Chris's solution first. Years ago before Chris offered these products there was a German guy in southern cal, that worked at a machine shop. He recommended the 3 bolt bearing and was shaving down the stock 73 and later shift rods to 3/4" with a lathe to support the bearing. The solution worked great, but as Chris mentions you have to remove the bearing every time you needed to remove the shift rod. I used double nuts on the rear, to make it easy to remove the bearing from the rear. When going to a 915 gear box, PMS sells a tunnel shift rod that is not adjustable. The adjustment as far as I know is done with the rear shift rod. There rear shift rod is designed for a Wevo. I went with Martin's 916 kit, so I bought Chris's adjustable tunnel shift rod. The adjustable shift rod works great with my 916 trans setup.