Small details

[HerronScott]

Randall,

Thanks for the pointer in the TR3 SPC. I would not have thought to look under "High Speed Equipment" for the 4.1:1 speedometer!

Chris's chart helps me with the rev/mile numbers that I was trying to collect as well. I do wonder whether he might have the /02 and /03 numbers swapped (KPH and MPH). TRA and Limora both show /02 to be MPH. Would love to find someone with either of those speedometers to confirm. Did TS39781LO have the original speedometer in it since it had a 4.1:1 axle from the factory and if so, which one did it have (bias-ply versus radial)?

Scott

 

[TR3driver]

Did TS39781LO have the original speedometer in it since it had a 4.1:1 axle from the factory and if so, which one did it have (bias-ply versus radial)?

I'd have to dig it out to be sure (the car is long gone), but IIRC the calibration number was 1344.

 

[Member 10617]

Is there a way to date these speedometers based on the SN numbers?

 

[TR3driver]

Here's a bit more information I just found:
https://www.scparts.co.uk/index/lang-2/lk...kal.tpl,x-a.htm

Seems like they have listings for all 3 ranges (S628, SN6307, SN6319) and the later ranges cover all combinations of kph/mph; axle ratio and radial/bias ply.

 

[HerronScott]

Randall,

Interesting, SCParts seems to use the same website layout and catalogs as Limora.

Ed,

Not sure if there's accurate documentation as to when the changes were made. The TRA Judging guide indicates there were changes at TS8637 (TR2 to TR3) and the TR3 SPC shows that as when the 4.1:1 axle and speedometer were available. I'm guessing the non SN xxxx/xx gauges might have been the ones used on the TR2 and the change to SN 6307/xx may have occurred with the change to the TR3.

The TRA Judging guide also indicates another change at TS10546 and the Nisonger catalog page I have indicated a change around May 1956 so possibly that was the change to the SN 6319/xx models. Seems like an awfully short run for SN 6307/xx though to me.

All theory though....

Scott

 

[Member 10617]

Randall and Scott,

Looks like trying to date the speedometers is complicated. But, unless I would be trying to restore a car for judging, it propbably isn't critical. Knowing the SN number and the axle ratio is enough for me.... and of course knowing the difference between TR3 and TR4 speedometers (but that can be seen by the change in the redline and where the "MPH" appears on the face).

Thank you very much for looking into this for me.

 

[TR3driver]

Did TS39781LO have the original speedometer in it since it had a 4.1:1 axle from the factory and if so, which one did it have (bias-ply versus radial)?

I should perhaps be clearer, I am only assuming that it originally had a 4.1 axle from the speedometer calibration and the later rear brakes (9" instead of 10"). I never bothered to pull the build record or anything like that.

And I was mistaken about that calibration, the speedo was SN6307/10 with a 1325 calibration. Working backwards from the numbers in "Practical Hints", that would appear to be for the Dunlop bias-ply tires rather than the Michelin X radials.