1 Speedometer Gear Tooth =?
Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 1,012
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From: Minnesota
1 Speedometer Gear Tooth =?
Is there a rule of thumb guiding the process of trying to calculate the speedometer? Going up or down 1 tooth in the gear equals aproximately what change in miles per hour?
SEMPER FI--1970 Dave
SEMPER FI--1970 Dave
Race Director
Joined: Mar 2001
Posts: 11,322
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From: Living in the Hartland
Re: 1 Speedometer Gear Tooth =? (1970 Dave)
Race Director
Joined: Sep 1999
Posts: 11,360
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From: Plano TX
Re: 1 Speedometer Gear Tooth =? (1970 Dave)
You have to do percentages. If you go from a 20 to a 21 tooth driven gear the ratio is 0.952 (20/21), so the speedo will show 4.8% less. Where the speedo used to show 60 mph it will now show 57. Where it showed 100 mph it will now show 95, etc.
Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 1,012
Likes: 0
From: Minnesota
Re: 1 Speedometer Gear Tooth =? (zwede)
Thanks guys --OUTSTANDING information. There truly is no end in sight, but an awful lot of satisfaction knowing 1. you have a great resource (The Corvette Forum) for advice and knowledge, and 2. getting the job done and knowing it has been done right. 
SEMPER FI--1970 Dave
SEMPER FI--1970 Dave
at 60mph
