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).
Performance issues and recommended adjustments for a car's jet restrictor, fuel system, and brake lever.
| Identifier | ExFiles\Box 46\2\ Scan115 | |
| Date | 1st April 1922 | |
| contd:- -5- The high speed jet restrictor found in this car was wrong in length; please have this checked and send to me and to Hy.{Tom Haldenby - Plant Engineer} Venturis of .675, .700, and .725, and suitable restrictors as suggested above - be sure they are large enough with the smallest throat to reduce the petrol below the normal amount so that we can be sure to get regulation. (We are at present troubled that we cannot cut down the HP. jet enough). Also the petrol level should not be too high. Hs.{Lord Ernest Hives - Chair} found difficulty in getting the top valve tappet cover off. It seems certain that we can reduce the length of the Autovac tank by 1" to 1¼" without making it too small. We found nearly a gall. of petrol in this tank - if we could be sure of half a gall. it would be enough to take us 10 miles. Hs.{Lord Ernest Hives - Chair} observes that the button on the top of the hand brake lever vibrates and makes a noise; could it have a small independent spring under it, and a conical seating on which it would rest when in the off position. When one does get a decent piece of road the car is very pleasing (fast and holds the road remarkably) but naturally it is not of the grand size that attracts the attention that our large one does. We easily climb to Bormes on the direct luffing up to 8 m.p.h. and do all the severe pieces of old back streets in Bormes on the second. I was very pleased to hear Hy.{Tom Haldenby - Plant Engineer} was getting along well up to 1.4.22. To realise over 300 miles per day on these roads we must expect trouble and one must go fast indeed. I should find 100 miles enough for me. I should have come home contd:e | ||