Corvette Tachometers . . . . .
The 1953 Corvette was the first American production car to support a tachometer as standard equipment. Like all Corvette gauges and clocks, tachometers are broken down into groups. Corvette tachs were mechanical units until 1975 when an electronic tach was introduced. Of the mechanical tachs, some were cable driven off a geared housing attached to the back of the generator. Others were cable driven off the engine distributor.
Mechanical Tachometers: These tachs were used from 1953 to 1974. The tachs were originally stamped on the housing or cluster back either as a "Registers Cable Speed" tach which was driven by the generator or as a "Registers Twice Cable Speed" tach which is driven by the distributor. These designations are used in the calibration of these units. Tach use was dependant on the horsepower of the Corvette. Below, described in a general nature, are the various years and tachometers for each. Click on years to see the various tach faces.
1953 to 1955 - 6 cylinder: This tach was placed in the center of the dash, about an arms length away from the driver. It may have not been in the optimal position but it was there to let the driver know what was going on under the hood. All of these tachs were of the "Registers Twice Cable Speed" type driven off the distributor. The plastic tach face read from 0 to 50 (5,000 rpm) in white numbers with no redline. The word TACH was in red lettering at the bottom of the face. The design of this tach included an inner tach face which included large dots to show each 1,000 rpm and a smaller dots in-between to show each 500 rpm and the words REV THOUSANDS for the rev counter. Much like an odometer, this rev counter would count engine rpm in each thousand revolutions. There was an outer plastic lens installed convexly. A heavy chrome bezel (used on all tachs '53 to '62) held the lenses in place and was attached to the housing with a crimped sheet metal bezel. An o-ring was used on all years to separate the lens and chrome bezel. These tachs included an inner bezel painted semi-flat black.
1955 to 1957 - 8 cylinder: This group of tachometers was basically the same as the 6 cylinder tach but with a higher rpm range. The white numbers now went from 0 to 60 (6,000 rpm) with no redline. This tach included the rev counter. All engine horsepower's used the same tach with the exception of the rare Fuel Injection option in '57. All of these tachs were of the "Registers Cable Speed" type driven off the generator except the Fuel Injected unit which was driven off the distributor and “Registers Twice Cable Speed”. The outer plastic lens was installed convexly and the inner bezel painted semi-flat black with the same chrome bezel.
1958 - The Corvette received a new instrument cluster in '58. Fitting in more with what a true sports car image should be, all main instruments were placed right in front of the drivers line of sight. This included the tach which is placed above the steering column, which was very easy to read. There are two groups of tachs used for this year. Now horsepower (HP) was playing a role in tach design. Low HP Corvettes had a tach face which read O to 60 (6,00 rpm) and now incorporated a redline at 5,300 rpm. This tach also included the rev counter. The tach was of the "Registers Cable Speed" type driven off the generator. A second tach was added to this year for high HP Corvettes. The tach face read 0 to 80 (8,000 rpm) with a redline at 6,500 rpm was used on the “Fulie” car and driven off the distributor. This tach did not include the rev counter so the inner face was changed. It still had the large and small dots but the word TACH was added in red and rev thousands taken off. The outer plastic lens was installed convexly with the inner bezel painted semi-flat black on both these tachs. The same chrome bezel was continued.
1959 to 1962 - Basically the same mechanical tach used since '53. This group of tachs differ with the face of the tach and the lenses used. Click on years to see variation in tach faces. These tachs had just the plastic lens but was now installed concavely. The various rpm ranges and red lines were now painted on a flat dished sheet metal plate. Low HP Corvettes were of the "Registers Cable Speed" type driven off the generator and the high HP Corvettes were of the "Registers Twice Cable Speed" type driven off the distributor. In 1962 with the addition of the new 327 cid engine, all tachometers were now driven off the distributor and calibrated for Twice Cable Speed.
1963 to 1967 - With the production of the new Sting Ray Corvette, a complete face lift was given to the instrument cluster. The tachometer and the speedometer were now large, the same size, and placed side by side in the drivers line of site. The tachs in this series are basically the same with some small mechanical differences. The '63/'64 are in a group as is the '65 thru '67. The cosmetic differences are in the type of face and needle used. The 63/64 tachs had a cast metal face with a deep cone insert in each face. The '63 having a brushed aluminum cone and the '64 having a semi-flat black ribbed cone. Because of this cone, the speed cup has a shorter shaft for the needle. So some of the internal parts are not interchangeable.The tach needle was unique for these two years as it had a "bent" shape. The tach face for the 65 thru 67 was made of flat sheet metal and the needle was a straight pointer. All of these tachs had a range from 0 to 7,000 rpm. The difference came in as to where the redline was placed, determined by the HP of the engine. Click on the years to see these different faces. Two '63 Corvette models, the 360 & 340 HP, came equipped with a buzzer tach. These special tachs were used through the first half of the year then it was decided that the engine produced too much noise to make these buzzers audible. The color of the red lines also differed with these buzzer tachs.
1968 to 1974 - The "Shark Style" Corvette came with a re-designed dash cluster. The tach and speedometer were in front of the driver but the smaller warning gauge were now moved to the center console area. The tachometers of this series were all mechanical and driven off the distributor. Mechanically these tachs are the same with the drive cable hook up changing from a screw on connection to a snap on connection in '69. From '68 to '71 the numbers and graduations on the face were pale green on a semi-flat black stamped sheet metal face. The numbers were raised slightly on this face. In '72 the color of the numbers and graduations were changed to a white color. Redline placement was dictated by the engine horsepower. Click on the years to see the various faces.
1975 to 1982 - 1975 marked the year that the Corvette changed to an electronic tachometer. The electrical distributor system was new and the tach was connected to the distributor electrically. There were two designs for the internal circuit boards on these tachs. One from '75 to 77 and the second from '78 to '82.