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[Gils TR]

I have a 1960 TR3A that has the stock 4-speed with overdrive and also came with the
4:11 rear end.  When we put the car back together we may have gotten a different TR3
speedo in the car than it came with.  Does the car I have take the same speedo as
all the other TR's?  If not...can anyone help me idenitify which speedo I need?
Current speedo seems to be 10 to 15 MPH off...and jumps a tad.  Thinking of getting
a rebuilt one...but would appreciate knowing what I am looking for.  Can this speedo
be reworked to work with my set up?  Input appreciated,  Gil Sissons

[charley fitch]

You can get your current speedo rebuilt to match the gear set up you have in your car.  If you contact The Palo Alto Speedometer Inc. at 1-650-323-0243 or at
 wwww.paspeedo.com  they can give you the information they need to recalibrate your speedo.  I had this done when I changed from 3.7 gears to 3.45 gears in the differential. A friend just had his speedo rebuilt by these same folks.  Essentially all you have to do is disconnect the speedo cable from behind the speedo and then move the car over a course of about 52 feet 9 inches(I think)and count the number of turns the cable turns in that distance.  They then use that to recalibrate your speedo.  They will also likely take the jump out of the speedo unless it is being caused by the cable, in which case a new cable would be  needed.  There are other dealers suce as Nisonger Instruments in New York that do this same work.  But I have not used them. 
One more advantage of rebuilding the speedo  is that you will be able to get the speedo reset to run with your current tire sizes. As we have not been able to get the original tires at reasonable rates most of us have changed tire sizes.
Good luck,
Charley Fitch 

[6TTR3A]

Gil,
The correct speedo for your TR is Smiths Jaeger 6319/04.  That number is located just below the pointer on the speedo face.  There is another number just above the opening on the face for the trip meter numbers.( Should be 1215 for a 411:1 diff) This tells the technician calibrating the speedo ON THE BENCH what the circumference of the tires is. As Mr Fitch mentions, great for original tires but no good for modern ones.
You really should start with the correct speedo--The speed can be corrected but the odometer and trip meter will be way off.
To arrive at what number to give the technician do the following;
Mark off EXACTLY fifty two feet, nine and five eights inches (52' 9 5/8") on a level surface. (That is 1/100th of a mile)
Disconnect your speedometer cable & hook up a home made device to count rotations of the cable. Divide your home made dial into tenths. Make sure your tires are correctly inflated & then either drive it for a few minutes at high speed OR overinflate the back ones by 5 pounds. Now get someone to watch your tires & roll the car over the measured distance, counting the number of rotations on your home made dial. The fractions of a rotation should be in tenths.  Multiply that number by 100 and that's the number you should give the technician to use instead of the number on the face.
 It is a good idea to replace the speedo cable while you're at it; it's probably the reason the speedo needle jumps or wanders.
Hope this helps.
FRank