speedometer gear change
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Joined: Oct 2013
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speedometer gear change
hi I have a 78 corvette with a turbo 350 transmission and a 3:08 rear axle ratio. I just purchased a 3:70 ratio rear axle . does anyone know what color speedometer gear I would need to keep my speedometer accurate? thanks for any help
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Try:
Performance Automotive Transmission Center (.net)
or
TCI Automotive (.net)
You will need to know how many teeth are on the Drive Gear right now and your tire dia. The Drive Gear is on the tailshaft of the tranny and is only visible after removing the speedo cable, driven gear, bullet assembley. Shine a flashlite in there and try to count the teeth and verify the color code of the drive gear.
In some cases, changing to a vast difference in axle ratios will require you to change the drive gear also. That requires removal of the driveshaft, tailshaft housing. Not fun, but do-able.
Performance Automotive Transmission Center (.net)
or
TCI Automotive (.net)
You will need to know how many teeth are on the Drive Gear right now and your tire dia. The Drive Gear is on the tailshaft of the tranny and is only visible after removing the speedo cable, driven gear, bullet assembley. Shine a flashlite in there and try to count the teeth and verify the color code of the drive gear.
In some cases, changing to a vast difference in axle ratios will require you to change the drive gear also. That requires removal of the driveshaft, tailshaft housing. Not fun, but do-able.
Melting Slicks
Joined: Sep 2004
Posts: 3,227
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From: Northeast
