TKX shifter location
 

I have an interesting issue that arose during the fitment of my Tremec TKX gearbox….

If I backup a little, quite some time ago I cut the hole in my transmission tunnel for the gearshift location. I positioned the cutout in the correct location as described in my car’s assembly manual. Given that my preferred gearbox back then was a Toploader, which has now been changed to a TKX because of clearance issues for the Toploader, however the shifter location for both gearboxes is close enough to be identical. Should be all good, yes?

So, the hole exists in what I believed to be the correct location for both boxes. The suggested location of the shifter on the TKX is the mid location of the three available, however I now find that the tunnel hole and the ‘mid’ shifter location do not line up at all.

Talking with Brett (BJ’s snake), his TKO uses the centre position for the shifter. Looking at and comparing the shifter location dimensions for the TKO and the TKX, they are identical. But, my TKX needs the forward location, which requires the purchase of an adaptor.

What I can’t work out is where the difference is. Brett uses an SBF engine and a TKO; mine uses an SBF and a TKX. Overall dims for both setups should be identical. Mine however, is about 100mm (4”) different in the mid position. I even checked to see if my gearbox was a TR-6060 supplied by mistake. No, it’s a TKX, and the 6060’s 3 shifter locations are very close to the TKO and TKX anyway.

More information… I believe also that ERA 289 cars using SBFs (what else 😉) use the middle position shifter location.

The answer might be staring me in the face, but I can't see it - I am at a loss.... so, my question - any ideas why my TKX shifter location is so different? It's not just a few mm, it's around 100mm / 4" !

Cheers!
Glen

Different bellhousing/scatter-shield dimensions possibly?

Cheers,
John

I don’t know anything about the TKX but are you turning the shifter around as one of the positions?
Larry

Glen,

Your shifter location is determined by your transmission’s tailshaft cross-member mounting point. The distance to the shifter locations from the tail shaft mount is the same for TKO and TKX transmissions. It may not be (most likely is not) the same as a top loader.

The rearmost shifter location on a TKO (or TKX) approximates the transmission tunnel entry point for a top loader, but, and this is important, it does not duplicate it. It only approximates it. The upshot is your shifter location position top loader to a Tremec (TKO or TKX) will be different than your original top loader and very likely require modifying your tunnel.

The center shifter location will provide you a shifter position near the front edge of the driver's seat and approximate a 289 car’s shifter location, but again not duplicating it. The center location will use a simple vertical shifter with no bend. If this is what you want, both Hanlon and Forte offer the necessary hardware to position the shifter in the center position.

The center position makes for a more natural shifting experience but does not look period incorrect. For that matter, some of the awkwardly bent shifters for use in the rear position do not either! In the for what it is worth bucket Kirkham has used the center-positioned straight shifter configuration option for customers since the billet car they built for Larry Ellison of Oracle fame and possibly earlier. I believe you need to ask for it. I don’t think it is the default shifter position. Predictably Kirkham’s center shifter is a Kirkham-originated design. They may or may not offer it for sale, I simply don’t know.

John, it's a quick Quick Time. I'm talking around 4" out with the location. There can't be that much difference in scattershield sizes.

Cheers,
Glen

Larry, yes the shifter can be turned around (and is turned around currently), and that puts the shifter in the mid position, and mine needs to be in the front location to have the gear lever in the right location viewed from above.
The front location is contrary to all other 289 installations that I know of.

Cheers,
Glen

I see! I know that in an original with a BW T-10, the shifter centerline is approximately 16.5 inches as measured from the front. So yeah, it would be too far forward to use the front shifter position. Interesting issue you’re having!

Larry

It's actually too far back when it's 'turned around' which actually puts it in the middle of the three locations available.
In this position, it is still about 4" too far back. The thing is, all other 289 (replicas) use that 'mid' position and it works for them perfectly. BJ's car (very similar to mine) uses the 'mid' position and his shifter is positioned perfectly. Mine, for some reason that hasn't hit me yet, is 4" too far back in the mid position. TKO and TKX (mine) are very close in dimensions, so I just can't work out why I need to use the forward most shifter location.

Ed, mine is a 289, and the centre position just does not work on my car. Why my application is different from other 289 cars, including another Pace 289 (BJ's car) and ERA 289s, I am at a loss to work out. The scattershield- as mentioned - is a QT; the tailshaft fits as it should; everything else matches where it should, but the centre location just does not work. Solution is of course to use the forward-most position of the three available, and all will be well.
However, I'm one of those sometimes irritating people who want to know "what's different" and why?" when the location and look should be the same as BJ's identical car, and all of the ERA 289 cars.

Cheers!
Glen

Glen,

A perplexing problem.

I would assume that Brett's (BJ’s snake) chassis and your chassis are identical, so the difference must be with the motor / gearbox configuration. Is it possible that the motor mount location for your FIA and Brett's FIA are different? I think this would be very unlikely.

- Are both of you running the same SBF block?

- If so, are you running the same motor mounts?

I suspect that once you compare your car & setup with Brett's, the difference of 4 inches will become apparent. My guess is the difference is ultimately due to the motor location.

It sounds like you can get the gearbox and shifter where you want them and that is all that really matters.


- Tim

Tim, yes Brett’s chassis and my chassis are identical. He has an SBF as well, however his induction is different to mine (mine is a standard efi setup), that would not have an effect on engine mounts. The scattershield dimensions and the gearbox dimensions (even though he uses a TKO and mine is a TKX) should be almost identical, yet there is a ~4” difference. 4” is a lot. I must be missing something.

Cheers!
Glen

Glen,

Did the 289 cars use top loaders or T-10s? I thought the top loaders were used for the 427 cars, and T-10s were used for the 289 cars.

Your transmission tunnel and your chassis are permanently attached to one another. That means the transmission tail shaft mount will determine the shifter positioning in the tunnel. That is unless you modify the tailshaft mounting point to move the transmission around.

The tailshaft mount is ground zero for the engine and bellhousing positioning. I might try calling or emailing Hillbank and ask them to weigh in on the shifter positioning conundrum. Over the years, I have had good experiences with Hillbank and questions like this.

Wait...
 

Paul and Ed,
I'm using a Tremec TKX now, instead of my preferred Toploader because of clearance problems with the shifter linkages on the side of the Toploader in the tunnel.

Cheers,
Glen

Glen, sounds like your motor and transmission mounts are further back. Does it seem alright in the forward position?

My memory is similar to yours, Paul. Although the tail shaft lengths changed, I seem to remember the tailshaft mount location remaining the same. Some boxes just had a longer tailshaft, but the basic transmission and its mounting points at the can and the chassis did not change.

The shifter location and tunnel opening mismatch is confounding ...

Jim, my engine mounts are where other Pace cars with Windsor engines have their engine mounts, and the trans mount is correct for my TKX, so 'no banana' yet ;)

Cheers,
Glen

Tell me about it :rolleyes:

Don't forget though, that I'm now using a TKX :D

Cheers!
Glen

Jim, engine mount locations are in the correct location (pre-drilled) which places the engine as far rearward in the engine bay as possible, and exactly as the design intention.

Cheers,
Glen

Maybe this helps.

Cheers