I quote the oil company you reffered to Rollo:
"One other exception is found in high-performance vehicles. The use of more complex computer algorithms in their engine control systems to control spark timing using one or more knock sensors, enables better performance on higher-octane fuel."
Regarding compression:As I said before NA-engines have higher C/R then SC-engines. this is because you have a larger combustion pressure in the SC-engine. If you convert your engine from NA to SC you hence need to lower your C/R.
So in short:
- Adaption can give your engine some extra power if you opt for higher octane.
- High compression engine, with high C/R, which are used in racing etc. do not have high C/R in mainly in order to benefit from a higher octanenumber, but in order to have a better swirl so that you can rev it more.
- Regarding diesel we want this fuel to ignite as quickly as possible and we measure this through the cetaneno.
- Regarding gasoline we want it to avoid autoignition for as long as possible.