Yeah, I am not sure if octane is the right word here, you are probably right in what you say. I just know that diesel fuel is much more resistant to detonation

Yeah, I am not sure if octane is the right word here, you are probably right in what you say. I just know that diesel fuel is much more resistant to detonation at high compression ratios, given how a diesel works. In a gas motor, octane gives a measure of this, so I used the word there, but as you say it is probably not the right word.