Replacing speedo driven gear
Thread Starter
Racer
Joined: Aug 2011
Posts: 429
Likes: 24
From: Charlotte NC
Replacing speedo driven gear
I think I'd like to swap my blue 20 tooth speedo gear for a brown 18 tooth, seeing that I'm reading about 1.12 miles on the speedo for every mile I drive. Also I'm not really sure where to look on the tranny to change it. I have a Borg-Warner super T-10 4 speed on a '74 BB. Thanks for any guidance on this!
Thread Starter
Racer
Joined: Aug 2011
Posts: 429
Likes: 24
From: Charlotte NC
I think I'd like to swap my blue 20 tooth speedo gear for a brown 18 tooth, seeing that I'm reading about 1.12 miles on the speedo for every mile I drive. Also I'm not really sure where to look on the tranny to change it. I have a Borg-Warner super T-10 4 speed on a '74 BB. Thanks for any guidance on this!
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From: New Or-leens Loo-z-anna
I think I'd like to swap my blue 20 tooth speedo gear for a brown 18 tooth, seeing that I'm reading about 1.12 miles on the speedo for every mile I drive. Also I'm not really sure where to look on the tranny to change it. I have a Borg-Warner super T-10 4 speed on a '74 BB. Thanks for any guidance on this!
I ask because my speedometer registers 90 mph when I'm actually doing 70 mph.
I'm wondering if I should go with more teeth or less teeth on the DRIVE gear that is located on the tailshaft, since there is such a large difference in actual speed/speedometer speed?
A/T shown (same principle though)......
Thread Starter
Racer
Joined: Aug 2011
Posts: 429
Likes: 24
From: Charlotte NC
O.K. So......going to LESS teeth on the DRIVEN gear "slows the odometer down"?
I ask because my speedometer registers 90 mph when I'm actually doing 70 mph.
I'm wondering if I should go with more teeth or less teeth on the DRIVE gear that is located on the tailshaft, since there is such a large difference in actual speed/speedometer speed?
A/T shown (same principle though)......
I ask because my speedometer registers 90 mph when I'm actually doing 70 mph.
I'm wondering if I should go with more teeth or less teeth on the DRIVE gear that is located on the tailshaft, since there is such a large difference in actual speed/speedometer speed?
A/T shown (same principle though)......
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,597
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From: New Or-leens Loo-z-anna
Drifting
Joined: Apr 2008
Posts: 1,305
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From: Lewisburg WV
thegazman
The drive gear stays the same diameter, just more or less teeth. And yes, more teeth on the driven gear slows the speedometer. However, be careful as a drive gear will only accept a limited number of different driven gear teeth before you also have to change the gear to more or less teeth. If you stay within a small range of number of teeth you shouldn't have any problem. If you try to correct a large problem, the drive and driven gears will not sync.
