Description
200-4R Speedometer Driven Gear. Comes in 26 to 31 tooth gear count.
Most cars with low rear end ratios will take a 10 tooth drive gear. The drive gear is part of the governor assembly which is located inside the oil pan. The gear can be replaced separately by removing the retainer clip on the governor shaft.
Main Speedometer Gear Page CLICK HERE
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Drive Gears |
Driven Gears |
|
10 teeth – green |
27 teeth – black |
|
11 teeth – orange |
28 teeth – yellow |
|
12 teeth – red |
29 teeth – green |
|
13 teeth – white |
30 teeth – blue |
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31 teeth – white |
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With 10 Tooth Drive Gear |
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| Axle Ratio | Tire Height | Driven Gear Teeth |
| 4.10 | 26 | 31 will work, but will read about 2 MPH fast at 50 MPH. |
| 4.10 | 27 | 31 |
| 4.10 | 28 | 30 |
| 4.10 | 29 | 29 |
| 3.73 | 26 | 29 |
| 3.73 | 27 | 28 |
| 3.73 | 28 | 27 |
| With 11 Tooth Drive Gear | ||
| Axle Ratio | Tire Height | Driven Gear Teeth |
| 3.73 | 27 | 31 |
| 3.73 | 28 | 30 |
| 3.42 | 26 | 29 |
| 3.42 | 27 | 28 |
| 3.42 | 28 | 27 |
| With 12 Tooth Drive Gear | ||
| Axle Ratio | Tire Height | Driven Gear Teeth |
| 3.23 | 26 | 30 |
| 3.23 | 27 | 29 |
| 3.23 | 28 | 28 |
To determine your tires true diameter in relation to determining what speedometer gears you need, measure from the ground up to the center of the axle then multiply by two. The actual run out of the tire can be as much as 2 to 3 inches less than what the circumference of the tire measures. In effect your tire has two diameters.
To determine your rear end ratio, raise both tires off of the ground, turn both tires at the same time one complete turn, at the same time count the turns of the drive shaft, this is your ratio.
