I am looking for some fairly detailed information on the clocks. Can anyone confirm whether the mounting bracket is the same or different for the 1968-71 clock vs the 1972-76 version? At first, I thought the mounting holes were identically spaced and placed and the only real difference between the clocks was the face and hands. However...

The mounting holes for the 1968-71 version are 93 mm apart from each other but I am starting to believe that the 1972-76 version holes are a bit further apart.

If anyone can confirm this difference, that would be great. If anyone can measure the actual distance between the two mounting holes on the 1972-76 version, that would be a HUGE help to me.

Thank you!

 

I'm not sure where you are getting the measurements, but the mounting holes are the same from 1963-1979. All these clocks used the exact same quartz conversion kit.

https://willcoxcorvette.com/corvette...sion-kit-63-82

This kit will fit every car 63-82.

Now what was the difference in the clocks. 1970 to 1979 clocks used a different reset pinion and a different reset pinion drive gear in the standard movement clocks.

The s-10 borg movement fit 1963-1969, the s-12 borg movement fit 1970-1979... Both are discontinued and no longer available.

I used to have boxes of the s-12 movements and they are sold out now... .

The difference was the pinion driven gear for the reset and the pinion reset gear. When we do the quartz conversions they come with two sets of gears, one is for the 10 tooth reset pinion gear the other is for the 12 tooth pinion gear. So you have to count the number of teeth on the reset pinion gear and that determines if you use red or black gears. Hope this makes sense.... but to answer your question there is nothing different about the mounting holes from 1963-1979. 1980-1982 cars used quartz clocks and used a different style of mounting the movement to the movement face plate. The thing is that when installing the movements in the mounting plate, they will only fit one way.

All clocks also had the same face mounting holes, you can take a 1968 clock and put a 1975 face on it. You'd have to change the re-set pinion gear or use the red gear set to do an installation. Again I hope this makes sense...

I've built these clocks for over thirty five years doing everything from repairing the original movements to quartz converting the clocks... If you go to youtube you'll find a video I did years ago on doing the quartz conversion.

Willcox

 

Thank you your for prompt reply. I really appreciate it.

I own the clock core in the photos below -- my understanding is that it is the 1968-71 model. I no longer need the core and I wanted to sell it, so I posted it as fitting not only 1968-71 but also 1972-76.

The person who bought it owned a 1973 Corvette -- he returned it to me and said that my clock was too small. I thought perhaps he didn't know what he was doing so I offered it for sale again and it was returned again by someone else who said the same thing -- that my clock was too small to be compatible the 1973-76 model.

As you can see in the photo below, the distance between the two mounting holes is roughly 93MM. Is that the standard distance for all clocks during this period? Can you think of any reason why the clock in the photos would not fit in a cluster for a 1973-76? Is there perhaps a second version of the clock for that period of time, similar to when 1969-70 Mustangs had both Deluxe and Standard clock options for the same model year?

Any suggestions would be much appreciated.

 

I have plenty of both clock cores in stock.... I'm not aware of any mounting hole variance in the clocks to the dash bezel. The issue is I can't check this for over a week, I'm 2200 miles from home right now. If you send me an email reminder after the 5th of July I'll check this for you but I really don't think there is any difference.

Willcox