1) increased stroke doesn't increase cylinder pressure (it increases
displacement and leverage).

2) increased bore increases displacement and allows the potential for valve
unshrouding.

3) increased compression increases cylinder pressure.

4) this is a VERY involved subject. our squishy pistons decrease cylinder
pressure, even though the engine's compression ratio is increased a LOT.
Compression is the before ignition pressure event, "cylinder pressure" is
effectively after ignition.

John
Aircooled.Net Inc.