Tach cable length
Thread Starter
Le Mans Master
Joined: Aug 2005
Posts: 6,529
Likes: 1,964
From: Temple Terrace Florida
Tach cable length
My tach. needle is bouncing around when I mash the gas pedal. Since the tach has been rebuilt, I think the problem lies with the reproduction cable. Another member had the same problem and shared with me the name of a company that makes in house cables in CO. They asked for the length of the cable. My problem is that the car is on the top bunk of the lift and the dash has to almost come out to pull the cable out. I plan to pull the dash to install LED lights, and I wanted to change out the cable at the same time. So, does anyone know the exact length of the tach cable? Thanks. Jerry
Burning Brakes
Joined: Mar 2012
Posts: 986
Likes: 169
From: Kingwood Texas
I’ve been having trouble breaking cables. I have a 63 and I believe it uses a 22” vs 25” for other mid years. To eliminate the sharp bend going in to the distributor, I purchased one of the elbows offered by most of the parts sellers. I measured and it and found that 20” looked right. I called the referenced fellow in Denver and he promptly made one of the desired length. So far, it seems to be working fine. And the quality is excellent. One of my breaks was caused by me being sent a 25” cable before I understood the difference. This required lots of bends to fit up. Broke quickly.
Im not at home for a week, but I could provide name and number of the cable maker if you send me a pm.
Im not at home for a week, but I could provide name and number of the cable maker if you send me a pm.
Le Mans Master
Joined: Dec 2004
Posts: 5,394
Likes: 2,767
From: Pittsburgh
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I believe Tampa Jerry runs a 66 Coupe.........
Instructor
Joined: Aug 2005
Posts: 141
Likes: 57
From: Alpena MI
The cable assemblies that are available from most vendors is 23 3/4" and will work for 63 - 67 mid year Corvettes. I've changed out the tach cable several times and it's a PITA without removing the cluster, but it is doable. Are you sure it's not the gauge? To check it, run a cordless drill in reverse to verify the gauge is working properly. I'd also check the distributor drive gear for excess end play or broken teeth. My 2 cents.
Thread Starter
Le Mans Master
Joined: Aug 2005
Posts: 6,529
Likes: 1,964
From: Temple Terrace Florida
Sorry about that, I have a 66 small block. I added the elbow at the distributor to take the stress off the cable. I also had the distributor rebuilt with a new drive gear. so I am confident that the gear is good. Can I assume that a 25" is the correct length? Thanks. Jerry
Race Director
Joined: Oct 2000
Posts: 12,667
Likes: 3,122
From: Shamong, NJ
According to the information I have, 63's came with a gray casing cable that was 24 3/4" long, 64's had a 22" off white casing cable, and 65-67's came with a black casing 23" cable. Big block and small block use the same cable. For many years, GM sold the black 23" 65-67 cable as a service replacement cable for all 63-67's. A can't say why there were different length cables, since the location of the firewall hole, tach and distributor is the same on all 63-67's. It may have something to do with the cut out in the shielding, or it might have just been the result of different suppliers?
