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 benefits of automatic spark advance and choke controls for automobile and aircraft engines.
| Identifier | ExFiles\Box 41\4\ Scan029 | |
| Date | 12th July 1930 guessed | |
| AUTOMOBILES AND OTHER VEHICLES Full automatic spark advance control Removes all necessity for manual dash or steering wheel control. Provides: Faster hill climbing and greater topping ability. Faster acceleration. Quicker getaway with cool engine with less handling of carburetor control. Higher road speeds. Increases mileage 15 to 35%. Doubles or better length of period before carbon removal. Increases valve life. Smoother action with fuels of low anti-knock value. A higher engine compression may be used for a given degree of smoothness resulting in increased power. Reduces service station errors in spark setting since factory sealed settings meet all requirements. Full automatic choke Removes entirely necessity for manual carburetor control. Permits a leaner carburetor setting at all times. Prevents flooding of engine with excess of fuel. Provides a smoother and faster starting and getaway than is possible with expert handling of choke or carburetor control. Cold engine performance is surprisingly free from backfire or rolling stagger. Undoubtedly the greatest difficulty encountered by the average driver and especially the new driver is the handling of the chok e or carburetor control during cool and cold weather starting and getaway periods. Many of the latest engines have increased this difficulty. AIRCRAFT ENGINES AND OTHERS Super-charged or over compressed engine control. Controls density of engine charge at all altitudes. Permits increased power (higher compression or greater super-charge) to be obtained from a given engine with safety at all times. Protects the engine from distruction when incorrect fuels are used, automatically throttling to the maximum safe power with a given fuel and altitude. Under certain conditions controls the mixture ratio for changes in altitude. Automatic choke may be a desirable addition to future engines. Automatic spark control protects normal and super density engines and increases mileage, increase depending upon the ratio of cruising speed to maximum speed. Indications are that an increase in mileage of 5 to 15% is possible. Due to accumulative nature of force available in this control the handling of magnetos has been proven possible without servo-mechanism. | ||