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 and cabin cooling, comparing radiator types and bonnet designs to prevent the car boiling and reduce hot floorboards.
| Identifier | ExFiles\Box 119\3\ scan0057 | |
| Date | 30th July 1914 | |
| Wor{Arthur Wormald - General Works Manager}/EH18/B30714. -2- July 30th, 1914 ing in very hot weather, because with all the improvements we can possibly make an ignorant driver will always be able to make the car boil, the driver can make more difference than we make by fixing larger radiators and louvred bonnets, it must be remembered that shuttered or louvred bonnets can only make any improvement when large quantities of air are passing through the radiator, if a driver keeps the fan speed and car speed low, then he would be just as well off with a plain bonnet. From our tests up to the present we should with the honeycomb radiator of standard size have a radiator which is more efficient than the present large Colonial type, but until we use the honeycomb I think we should still fit the large radiators and louvred bonnets to Colonial cars; we know that these have prooved themselves to be satisfactory. Floor Board Temperatures. It will be seen that the shuttered bonnet will also halp to keep the floor boards cool. I do not think for one minute that it will stop complaints of hot floor boards, the improvement is only about 5%, I doubt very much if one could appreciate that amount of difference. On cars with large radiators and louvred bonnets we still have complaints of hot boards and they are better than the shuttered bonnet will be. The only means I know of to keep cool floor boards is to make the wind-screen into a ventilator, or hang the side door on the rear pillar and fix it partly open so that it acts as a large ventilator, Unless there are large ventilators in the scuttles the car rushing through the air causes a vacuum which | ||