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).
Engine cooling system limitations and overheating issues on a 40/50 HP car during a trip in France.
| Identifier | ExFiles\Box 24\4\ Scan158 | |
| Date | 13th August 1924 | |
| COPY OF MEMORANDUM PN{Mr Northey}3/KW13.8.24. To CJ. from PN.{Mr Northey} Copy to BJ. ENGINE COOLING SYSTEMS. I have just returned from France, having run about 1000 miles on one of our 40/50 H.P. standard cars. Probably owing to the fact that my motoring in France has been nearly all done during winter months, I have been very much surprised, in fact shocked, at our very desperate limitations when motoring on the Continent during summer months, arising from provision made by us in respect of engine cooling. I was not aware, I did not appreciate, that it would not be possible to run for, say 20 minutes at full throttle on a flat straight road in still air, without losing water by boiling at the end of that time at such a rate that one would be forced to refrain from opening the throttle more than half its full capacity. Obviously the conditions become much more onerous if it happens that a fairly warm wind is blowing in the same direction as the car is moving ahead. From Dreux to Chartres, a distance of 34 kilometres, the road is quite straight and level for 22 kilometres, and has no turning into it during that distance. Imagine an owner of a Rolls Royce car, capable of running at, say, 70 miles an hour, being forced to reduce his speed down to 45 miles an hour over the second half of this length of road simply because his water is boiling dangerously. Meanwhile all other makes of cars that one is likely to see on the Continent will be passing in the same direction without boiling. As you are aware, it has always been a sore point with owners, when using their Rolls Royce cars in mountainous districts, that they had trouble with overheating, when other cars much cheaper do not have this same amount of trouble, but I did not realise to what extent this disability existed with our standard production. The two journalists with me, one representing the "Autocar", and the other the "Daily Telegraph", naturally wished at Lyons - being half a day's run from the mountains - to see our much talked of car performing on one or other of the Historic Passes, which during the winter are not easily available for motorists. I therefore had no alternative but to express willingness to drive over the Col du Lauterets and the Col du Galibiers, the former Pass being 6,500 ft., and the latter rising to 8,500 ft., Nothing could have been | ||