1966 speedo and tach cables orig factory line, repro or NORS

[John R.]

Did the 1966 factory installed speedo and tach cable look like the ones in the photos below or are these NORS or reproduction? Thank you.

BTW, the first photo is the speedo cable and the second it the tachometer cable.

[David L.]

Re: 1966 speedo and tach cables orig factory line, repro or NORS

John,

Attached are 4 different photos of the 2 ends on my tach cable that was on my 1966 Corvette when I bought it in 1979 BUT I do not think that it is original.
Photo #1, nut diameter = 1"
Photo #2 crimped part measures 1.23" long, nut diameter = 1".
Photo #4 is a duplicate of #3. (Rookie mistake), nut diameter = 3/4"
Photo # 5 crimped part measures 1.50" long, nut diameter = 3/4"

The casing length measures 24" long (excluding the 1" nut and the 3/4" nut).
The cable measures 25 1/8" long.

The part number in the 1966 AIM is 3866126 as well as my 1966 and 1967 Chevrolet Parts Catalog which describe the shaft length as 23" and the cable length as 24 1/8".
GM # 3866126 was replaced by GM # 6476986 in March 1970.

Dave

[Edward J.]

Re: 1966 speedo and tach cables orig factory line, repro or NORS

John look at the fittings that screw on, it appears like I see some part numbers, that may give you a clue.

[John R.]

Re: 1966 speedo and tach cables orig factory line, repro or NORS

Edward, that is AC Speedometer which is embossed on the serrated nut/fitting.

[Edward J.]

Re: 1966 speedo and tach cables orig factory line, repro or NORS

John they must be the real deal, I am not 100 % someone like Joe L. would know, I think the service replacement one's may not have the embossing.

[David L.]

Re: 1966 speedo and tach cables orig factory line, repro or NORS

I just checked the tach cable that I removed from my 1966 Corvette that I bought in 1979. Each serrated nut/fitting has " AC SPEEDOMETER" cast on the perimeter. I do not think mine is original equipment (GM # 3866126) since the shaft measures 24", cable 25 1/8". GM # 3866126 is described with a 23" shaft length and 24 1/8" cable length.

According to Chevrolet and GM Parts History:
3866126 replaced by 6476986 in Mar. 1980......6476986 (23" shaft, 24 1/8" cable) used on 68-69 Ser. 10-30 trucks
6476986 replaced by 6480368 in 1979 or 1980.........6480368 used on 1976 Cadillacs cruise control

There is no connection between 6480368 and 6478117 in any of my Chevrolet and GM Parts History manuals (complete from 1965 to 1990).

6478117 (AC CC500, 24" shaft, 25 1/8" cable) appears in Sept. 1974 Corvette Parts Catalog for 63-67 Corvettes
6478117 replaced by 6480367 (AC CC701, 24" shaft, 25 1/8" cable) sometime between Jan. 1978 and June 1979

In the early 1980's I purchased tach cable # 6480367 (AC CC701) from my local Chevrolet dealer for my 1966.

[John R.]

Re: 1966 speedo and tach cables orig factory line, repro or NORS

David, thanks. By shaft do you mean housing length including the metal crimped ends? If so, my tach is approximately 24". Above you state 23" is correct for 3866126 which I assume is the correct part number for 1966 and perhaps other midyears. But later you state that the 6478117 was showing 24" shaft and for 63-67 vettes. So does this mean factory tach cable shaft length was 23", but later service replacement tach cables were 24" shaft length?

[David L.]

Re: 1966 speedo and tach cables orig factory line, repro or NORS

David, thanks. By shaft do you mean housing length including the metal crimped ends? If so, my tach is approximately 24". Above you state 23" is correct for 3866126 which I assume is the correct part number for 1966 and perhaps other midyears. But later you state that the 6478117 was showing 24" shaft and for 63-67 vettes. So does this mean factory tach cable shaft length was 23", but later service replacement tach cables were 24" shaft length?

John,
Yes, the shaft length includes the crimped ends. The cable is 1 1/8" longer than the shaft. This is also stated in some of my many Chevrolet Parts Catalogs. GM # 3866126 is listed in the 1966 AIM as well as in my 1966 Chevrolet Parts Catalog which describes the shaft length as 23" and the cable length as 24 1/8". According to my other parts catalogs the first replacement cable, GM # 6476986, is 23" shaft length, etc., same as GM # 3866126. The other 63-67 replacement cables, 6478117 and 6480367, cables are 24" shaft and 25 1/8" cable.
Dave