10:1 detonation

[brien23]

If detonation is a result of high compression with a 10:1 engine with a leak down test in the 60 to 65 range, is that engine still susceptible to engine detonation on lower auto fuel octane around 92 over 100LL?

 

[PaulMillner]

If detonation is a result of high compression with a 10:1 engine with a leak down test in the 60 to 65 range, is that engine still susceptible to engine detonation on lower auto fuel octane around 92 over 100LL?

Yes, that engine will detonate on mogas. The leak down test tells you if the rings will prevent excess blow by... the impact on effective compression ratio is very small, as the short, high pressure combustion event's peak pressure will NOT be appreciably affected by even very leaky rings.

Paul