Tire Size Finder (optional):
Stock Sizes
- 255/75-16
Plus Sizes
- 255/75-16
Accepts P-Metric and Inches
| 80/90-21 | 120/80-21 | Difference | |
|---|---|---|---|
| Diameter inches (mm) | 26.67 (677.4) | 28.56 (725.4) | 1.89 (48) 7.1% |
| Width inches (mm) | 3.15 (80) | 4.72 (120) | 1.57 (40) 50% |
| Circum. inches (mm) | 83.78 (2128.11) | 89.72 (2278.91) | 5.94 (150.8) 7.1% |
| Sidewall Height inches (mm) | 2.83 (72) | 3.78 (96) | 0.94 (24) 33.3% |
| Revolutions per mile (km) | 756.23 (469.9) | 706.19 (438.81) | -50.04 (-31.09) -6.6% |
Speedometer Difference
| Speedo Reading | Actual Speed |
|---|---|
| 20 mph (32.19 km/h) | 21.42 mph (34.47 km/h) |
| 25 mph (40.23 km/h) | 26.77 mph (43.08 km/h) |
| 30 mph (48.28 km/h) | 32.13 mph (51.7 km/h) |
| 35 mph (56.33 km/h) | 37.48 mph (60.32 km/h) |
| 40 mph (64.37 km/h) | 42.83 mph (68.94 km/h) |
| 45 mph (72.42 km/h) | 48.19 mph (77.55 km/h) |
| 50 mph (80.47 km/h) | 53.54 mph (86.17 km/h) |
| 55 mph (88.51 km/h) | 58.9 mph (94.79 km/h) |
| 60 mph (96.56 km/h) | 64.25 mph (103.4 km/h) |
| 65 mph (104.61 km/h) | 69.61 mph (112.02 km/h) |
| 70 mph (112.65 km/h) | 74.96 mph (120.64 km/h) |
| 75 mph (120.7 km/h) | 80.31 mph (129.25 km/h) |
| 80 mph (128.75 km/h) | 85.67 mph (137.87 km/h) |
| 85 mph (136.79 km/h) | 91.02 mph (146.49 km/h) |
| 90 mph (144.84 km/h) | 96.38 mph (155.1 km/h) |
| 95 mph (152.89 km/h) | 101.73 mph (163.72 km/h) |
| 100 mph (160.93 km/h) | 107.09 mph (172.34 km/h) |
| 2.35 | 2.73 | 2.94 | 3.07 | 3.21 | 3.31 | 3.42 | 3.55 | 3.73 | 3.91 | 4.11 | 4.27 | 4.56 | 4.88 | 5.13 | 5.29 | 5.38 | 5.71 | 6.17 | 7.17 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1797 | 2088 | 2248 | 2348 | 2455 | 2531 | 2615 | 2715 | 2852 | 2990 | 3143 | 3265 | 3487 | 3732 | 3923 | 4045 | 4114 | 4367 | 4718 | 5483 |
Better Fuel Economy Factory Ratios Increased Power
