Trend in Combustion Chambers and Fuel Systems 470223
COMPRESSION ratios will increase gradually to about 8:1 for small spark-ignition engines and 7:1 for large engines as fuel improvements permit, engineers estimate. This increase will probably be accomplished with some sort of valve-in-head design. The higher ratios will call for better cooling to prevent detonation and more rigid construction for shock control. The tendency toward increased deposits will be curbed by better piston rings, closer-fitting pistons, cooled valves, and cooled spark plugs.
In fuel systems, the ultimate aim is a simple, easily serviced, moderately priced fuel-injection system. Meanwhile, pressure carburetion is likely to be the next advance. Fuel pumps in or near the tank would give the higher pump pressure needed for pressure carburetion and improve atomization and distribution.
Supercharging to increase power by raising compression pressure instead of compression ratio will be thoroughly investigated.