Comparison table of engine RPM at 60 MPH for various cars based on tyre size and axle ratio.
| Identifier | ExFiles\Box 156\4\ scan0136 | |
| Date | 3rd November 1943 guessed | |
| ENGINE R.P.M. AT 60MPH CLAN GARAGE CARS | CAR | TYRE SIZE | ROLLING CIRCLE | ROLLING CIRCLE | ROLLING CIRCLE | ROLLING CIRCLE | AXLE RATIO | RPM AT 60MPH | RPM AT 60MPH | RPM AT 60MPH | |---|---|---|---|---|---|---|---|---|---| | | | STATIC (MEASURED) | STATIC (DUNLOP CHART) | 30 MPH (DUNLOP CHART) | 60 MPH (CALCULATED) | | BASED ON MEAS. STATIC R.C. | BASED ON CALC. 60MPH R.C. | SERVICE AVERAGE | | 8BV | 6.50X16 | 87.75 | 86.38 | 87.32 | 88.26 | 4.1/1 | 2969 | 2951 | 2960 | | 9BV | 6.50X16 | 86.625 | 86.38 | 87.32 | 88.26 | 4.1/1 | 3007 | 2951 | 3000 | | 10BV | 6.50 X16 | --- | 86.38 | 87.32 | 88.26 | 4.3/1 | --- | 3087 | 3090 | | 11BV | 6.50X16. | --- | 86.38 | 87.32 | 88.26 | 3.7/1 | --- | 2675 | 2680 | | 12BV | 6.50X16 | 88.0 | 86.38 | 87.32 | 88.26 | 4.1/1 | 2952 | 2943 | 2950 | | B22AW | 6.50X16 | 86.625 | 86.38 | 87.32 | 88.26 | 4.3/1 | 3146 | 3087 | 3120 | | 1B50 | 7.00X16 | 90.25 | 88.90 | 90.16 | 91.41 | 4.3/1 | 3019 | 2982 | 3000 | | 2B50 | 7.00X16 | 89.00 | 88.90 | 90.16 | 91.41 | 4.1/1 | 2927 | 2850 | 2900 | | 3B50 | 6.50X16 | 86.625 | 86.38 | 87.32 | 88.26 | 3.7/1 | 2727 | 2675 | 2700 | | 3B50 | 7.00X16 | 89.50 | 88.90 | 90.16 | 91.41 | 3.7/1 | 2638 | 2584 | 2600 | | 4B50 | 7.00X16 | 89.00 | 88.90 | 90.16 | 91.41 | 4.1/1 | 2927 | 2850 | 2900 | | 30GVII | 7.00X16 | 90.00 | 88.90 | 90.16 | 91.41 | 3.7/1 | 2624 | 2584 | 2610 | | 33GVII | 7.00X16 | --- | 88.90 | 90.16 | 91.41 | 3.7/1 | --- | 2584 | 2580 | | 33GVII | 7.30X16 | --- | 91.11 | 92.68 | 94.26 | 3.7/1 | --- | 2505 | 2500 | | LR {Mr Ellor} 1 | 6.50X16 | 86.625 | 86.38 | 87.32 | 88.26 | 3.7/1 | 2727 | 2675 | 2700 | | LRTI | 6.00X16 | 83.25 | 84.18 | 85.13 | 86.08 | 4.3/1 | 3198 | 3165 | 3170 | | AUSTIN MYTH | 5.25X16 | 80.25 | 78.86 | 79.80 | 80.74 | 5.5/1 | 4342 | 4316 | 4330 | | AUSTIN 10 | 5.25X16 | 80.00 | 78.86 | 79.80 | 80.74 | 5.3/1 | 4188 | 4158 | 4180 | | AUSTINS. | 4.75X17 | 83.50 | 82.00 | 82.64 | 83.26 | 5.5/1 | 4174 | 4186 | 4175 | | VAUXHALL 10 | 5.00X16 | 78.25 | 78.23 | 78.86 | 79.48 | 5.0/1 | 4048 | 3986 | 4000 | | LANCIA | 5.25X16 | 79.75 | 78.86 | 79.80 | 80.74 | 4.1/1 | 3257 | 3218 | 3240 | | STUDEBAKER | 5.50X16 | 82.50 | 81.06 | 81.70 | 82.31 | 4.6/1 | 3533 | 3541 | 3540 | | MYTH | 5.00X16 | --- | 78.23 | 78.86 | 79.48 | 4.88/1 | --- | 3890 | 3890 | | RIPPLETTO 14 | 6.00X16 | --- | 84.18 | 85.13 | 86.08 | 4.66/1 | --- | 3357 | 3360 | | ||
From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).