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).
The performance and issues of the S.I. Spectre vehicle.
| Identifier | ExFiles\Box 91\4\ scan0158 | |
| Date | 29th July 1935 | |
| HOTEL DE FRANCE. CHATEAUROUX, Indre. France. GWH{George W. Hancock - Head Chateauroux}/2/JAB. 29th July 1935. To. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} From. G.W.H. S. S. I. SPECTRECodename for Phantom III. We have received your memos. of 26th & 27th inst. 1) How do we know the tappets are not wearing. We cannot tell you definately without seeing them. The Auto adjustment certainly looks after the clearance, but one can release the plunger and measure the rocker arm clearance, before starting out each morning. We have not made a definate practice of it, but we have checked them especially after the Cylinder head was refitted when we found two Walves open, due to the Cylinder head not being firmly down. Valve clearances can be checked as previously but takes a longer time. We are pleased to hear a better job has been made with chromium plated tappets. 2) Fisher did leave the V M 20 Clutch linings, but they are Ferodo. The present linings are now definately causing a jagger. We cannot reverse or get away really smoothly, without the transmission clatter. 3) Your remarks re maximum power is interesting. Have you found the air pots full of oil from the rocker case ? We are getting it badly. 4) DETONATIONS. Yes I tried the Car yesterday with a full load and had to retard the ignition three to four notches. Esso petrol, Azure petrol is not prone to detonation. I do not think we could stand any more compression. 5) BRAKES. With the increased leverage to the front brakes, we are of the opinion that the braking is good. 6) MAXIMUM REVS. Sorry we have not a rev counter fitted. The Speedometer has been up to 92 MPH. down hill. With favourable conditions 90 has been reached on the level. This is after we had retimed the ignitions when I reported increase of power. Revs. maximum 4.040 Axle ratio 3.34 Wheel radious at 35 lbs. 15". | ||