I just want to make sure I'm not doing something stupid here.

I have an original 69 tach with a 6K red line and 7K sweep, which is in nice cosmetic condition. It sitll has the ink stamps on the back (6469383, JK2J, and something else I can't read in my photos).

My car has a Dave's small body HEI, and the tach has not worked since installed. Needle doesn't move at all. Tried installing a filter and it did nothing.

My options are:

Buy a repro tach for $195 or so, which may or may not work with the HEI without a filter. Filter is cheap to build.

Send my original to Auto Instruments and have it converted for $175, and it's sure to work out of the box.

The reason I am asking is because I have seen the original early Z/L78/L89 tachs sell for big money, but since I can't verify if mine works on a non-HEI car, I don't know if mine is worth more than a repro costs, and I should sell it to someone who cares about originality.

No wonder I can't get the car off to paint, given my bosession over little things like this.... :)

Eric, If I had my car avail, I would have you try it on my car.

D & M Restoration in Greenville SC repaired my original tach.
www.dandmrestoration.com
He said if the repair didn't hold he could replace the circuitry with new, but I don't remember that cost. I liked that he personally preferred saving the original circuits instead of just replacing them.

Kevin - thanks for the thought...

Andrew - I spoke to Mike at D&M, and he quoted $265 to 285 to repair. It's all more than I wanted to spend (was hoping the tach would work right away), but AutoInstruments seems to do good work as well, and they are $100 cheaper.

I guess it makes sense to just have mine converted, because then I'll know it works, and it matches the appearance of the original speedo nicely. I couldn't care less about the "correct" redline/sweep...once folks see the BB and 123 VIN, having the correct tach won't matter much. I just didn't want to have this one fixed and then find out they sell for $300 even if they are not confirmed as working.

I need to call my local gearhead buddy and see which distributor he has in his Chevelle...

Eric, that tach only came in the early Z/28 and the 396/375 models. I would for sure hang on to it. Thats whats in my early 10D Z/28