Tachometer Issues
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Heel & Toe
Joined: Oct 2017
Posts: 21
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Tachometer Issues
Aargh, I have a 73 and yesterday my tach started making noise and then the needle starting jumping all over the place . . . I have an MSD Electronic Ignition w/mechanical tach option . . . thinking about replacing the whole thing with an electronic tach . . . has anyone done that ??? was it hard to do ????
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From: New Or-leens Loo-z-anna
And make sure the ends of the flexible drive core aor not frayed and also engage the female ends well. Also make sure the cable itself isn't in a bind from being positioned incorrectly.
Thread Starter
Heel & Toe
Joined: Oct 2017
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Thanks for the suggestion but I already tried lubing the cable (checked the distributor end and it looks fine) - it seemed to make a difference at first but after driving about a mile it started making noise again so I suspect the years have taken their toll on the cable. I have given thought to replacing the cable it giving the effort that takes, I was considering going to an electronic tach (probably use the zip-corvette conversion kit) so I was wondering if anyone has done that and how hard it was to do.
Thread Starter
Heel & Toe
Joined: Oct 2017
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Thx- I Thought about that cause a new cable is the cheapest solution but since I have to tear into the dash to do that I wanted to know if anyone has done an electronic conversion and whether they thought it was worth it
Race Director
Joined: Sep 1999
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From: Plano TX
I converted the tach on my '71 to electric. It's easy and the electric tach is much better than the mechanical one ever was. I used a '75-'77 tach as it bolts right in and then put an early face plate on it as I wanted a 6k redline (modified engine).
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Le Mans Master
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I had/have a MSD Tach Drive 8572.
When I went to the RamJet 350 with MEFI -- I converted the tach to a 75-77 tach since it used a GM small cap efi distributor.
When I went to EZ-EFI 2.0; I then went back to my MSD 8572 distributor, locked it out, and I now use it with my MSD box to drive my same electric tach. (NOTE: With signal coming from MSD box- I had to remove the tach filter because otherwise it would start bouncing above 3500-4000 rpm...nice and steady now).
If I was going to an electric tach nowadays, then I would look for one of those conversion kits that alter your mechanical tach drive.
Here you go:
https://willcoxcorvette.com/corvette...-kit-1955-1974
Mine ended up costing about this much after I bought the replacement tach and the replacement board (old board was bad).
When I went to the RamJet 350 with MEFI -- I converted the tach to a 75-77 tach since it used a GM small cap efi distributor.
When I went to EZ-EFI 2.0; I then went back to my MSD 8572 distributor, locked it out, and I now use it with my MSD box to drive my same electric tach. (NOTE: With signal coming from MSD box- I had to remove the tach filter because otherwise it would start bouncing above 3500-4000 rpm...nice and steady now).
If I was going to an electric tach nowadays, then I would look for one of those conversion kits that alter your mechanical tach drive.
Here you go:
https://willcoxcorvette.com/corvette...-kit-1955-1974
Mine ended up costing about this much after I bought the replacement tach and the replacement board (old board was bad).
Last edited by carriljc; Nov 20, 2017 at 10:59 AM. Reason: add link and clarify some statements
Thread Starter
Heel & Toe
Joined: Oct 2017
Posts: 21
Likes: 0
I had/have a MSD Tach Drive 8572.
When I went to the RamJet 350 with MEFI -- I converted the tach to a 75-77 tach since it used a GM small cap efi distributor.
When I went to EZ-EFI 2.0; I then went back to my MSD 8572 distributor, locked it out, and I now use it with my MSD box to drive my same electric tach. (NOTE: With signal coming from MSD box- I had to remove the tach filter because otherwise it would start bouncing above 3500-4000 rpm...nice and steady now).
If I was going to an electric tach nowadays, then I would look for one of those conversion kits that alter your mechanical tach drive.
Here you go:
https://willcoxcorvette.com/corvette...-kit-1955-1974
Mine ended up costing about this much after I bought the replacement tach and the replacement board (old board was bad).
When I went to the RamJet 350 with MEFI -- I converted the tach to a 75-77 tach since it used a GM small cap efi distributor.
When I went to EZ-EFI 2.0; I then went back to my MSD 8572 distributor, locked it out, and I now use it with my MSD box to drive my same electric tach. (NOTE: With signal coming from MSD box- I had to remove the tach filter because otherwise it would start bouncing above 3500-4000 rpm...nice and steady now).
If I was going to an electric tach nowadays, then I would look for one of those conversion kits that alter your mechanical tach drive.
Here you go:
https://willcoxcorvette.com/corvette...-kit-1955-1974
Mine ended up costing about this much after I bought the replacement tach and the replacement board (old board was bad).
Burning Brakes
Joined: Nov 2006
Posts: 893
Likes: 7
From: Orange Park Florida
have you checked the drive gear in the distributor? I had to replace mine several years ago. Remove the cable at the distributor then remove the gear housing. Examine the gear teeth and look for excessive wear.
Thread Starter
Heel & Toe
Joined: Oct 2017
Posts: 21
Likes: 0
thanks Jim, I just put a new msd distributor in so I'm hoping it's just the cable - I have one on order and have my fingers crossed