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).
Required slipper wheel diameter for the Goshawk 11, pending tests with heavier cast iron pistons.
| Identifier | Morton\M1.1\ img067 | |
| Date | 1st October 1921 | |
| R.R. 235E (100 T&S.H. 7987 10-12-20) C.2948 FROM THE ORIGINAL Hsl/LGl.10.21. X4219 X4244 GOSHAWK 11. With reference to your telegram asking whether 8.15" diameter Slipper would be large enough for Goshawk 11. At present we are not able to say. We are running the car with a standard 40/50 H.P. Slipper which is 11" dia. We anticipate that we shall be able to reduce this considerably but we have not made our tests until we get the cast iron pistons because if we use the heavier piston the wheel may have to be larger. We have some cast iron pistons practically ready. We ought to be able to let you have the information you ask for on Wednesday or Thursday next week. Our recommendation is that you are not stingy in the size of the Slipper Wheel. Hs.{Lord Ernest Hives - Chair} | ||