[solarguy]

Ferdinand Porsche tried something similar, with some pistons super charging other pistons.

I think it was given up as overly complex and had overheating problems.


I just bought a Mazda 3 with the Skyactiv system. Instead of typical gasser compression ratio of 9:1 or 10:1, the US version has 13:1, and the euro or japanese version is 14:1.

To prevent engine destroying pre-ignition, they use active changes in the cam timing.

So far, it works a treat.