time2roll wrote:
Have read some on the rotary valves. Must be something holding it back.
Rotary valve do not seal as well as poppet valves. Unburned fuel can leak out the exhaust and combustion gases can leak into the intake manifold.
Rotary engines (Wankel/Mazda) do not use rotary valve. They have a port that is covered and uncovered as the rotor turns. Again, the seal is not as good as a poppet valve.
Most modern engines use variable valve timing which is a BIG improvement over fixed valve timing !
time2roll wrote:
Latest I have read is on microwave/plasma ignition instead of the spark plug.
Plasma ignition and electric valve actuation have been the "holy grail" since I was in college and that was a LONG time ago !
