1972 Electronic Tach Conversion Issue
Thread Starter
Instructor
Joined: Oct 2012
Posts: 222
Likes: 11
From: Johnston, Rhode Island
1972 Electronic Tach Conversion Issue
A couple of months ago I had the mechanical tach in my car converted to an electronic one. My car has an HEI and the original tach didn't work with the ignition upgrade. The tach was installed by a reputable Corvette Specialist. The problem is the tach is a little jumpy. When the car is idling it stays normal for a while than jumps up then down. When accelerating it moves up in a jumpy fashion, not smoothly as it I would think it should be. And when I turn the car off the needle doesn't settle at zero it sets at about 1000 rpm. If I turn the key to the on position, but don't start the car it drops to zero. Is this normal for an electronic tach conversion in an old Corvette? Thank you.
Le Mans Master
Joined: Jan 2001
Posts: 6,689
Likes: 1,365
I did it the conversion on my 1968
And it is not jumpy.
Did you install a Tach Filter?
They're easy enough to fabricate (a couple of bucks in parts). If you need the diagram I can look for it for you. It's on this forum somewhere.
Did you install a Tach Filter?
They're easy enough to fabricate (a couple of bucks in parts). If you need the diagram I can look for it for you. It's on this forum somewhere.
