Chronometric Tachometer

[Tom Kirkham]

I was just thumbing through the latest Racer Wholsale catolog a came accross a "Stak chronotronic" which is an "accurate replica of original chronometric tachometer"

Some of the 289 comp Cobras used Smiths chronometric tachs. I also believe the Smiths chronmeterics were optional on the 427 Comp cars.

The tach (part number ST901096) is $590.00 from Racer Wholesale.

[Byots]

Tom - FYI, the '65 Shelby American parts book lists something like 6 or 8 different tachometers. Maybe one or two were for the Mustang GT350 and the rest were Cobra options, those being mechanical and electric (both showed various manufacturers). I recently acquired one of the extremely rare original mechanical Smiths tachs that's listed in the catalog as a "race" option - it was obviously made as an exact replacement being the same 4" dia and style, right down to the hollowed out tick marks, which Nisonger and others have said was unique to Cobra gages. This is a magnetic tach though, which old Smiths documents show is the type preferred by racers (more accurate during transient engine speed, protects from overspeed better).

Nisonger said the chronometric Smiths tachs were only available in 3" or 5" diameter, and Bill Murray said some 289 cars he's seen with Chronometrics had adapter rings to hold a smaller tach in the larger dash hole........

[csx700?]

byots
please list the types of tachs used. thanks...........john

[Byots]

Smiths, Sun, Stewart Warner, one listed under a SA P/N with supplier as "Sullivan", and Rotunda

[Byots]

Some may have just been 289, 427 or both 289 and 427, which is not easy to tell, as well as I have learned the catalog is not always complete.

[csx700?]

thanks byots
i believe the "sullivan" is the jones / motrola tachs.

[Byots]

What information do you have which leads you to believe it's a Jones/Motorola piece?

[Rick Parker]

Several of the FIA and USRRC cars that I have seen used cable driven tachs. Imo these were still commonplace in the race scene with electric ones subject to vibration and electrical gremlins. It was just a way to eliminate a potential problem at the time. Gratefully electric tachs have come a long ways.


Rick