there are usually gains to be had using higher octane, up to a certain point.Ridgemanron said:I was under the impression that octane over the 'stated manufacturer's level' actually adds nothing. I do remember reading that octane must be no lower than the recommended amount but that
additional levels were a waste of money.
Any confirmed data on this?
I think they are going with the theory that the car will advance timming to max. With the higher octane the vehicle would be less likely to ping under heat and stress thereby allowing max advance and avioding any timming retard issues. If the timming is at max advance the vehicle will make more power. Although your boosted thoughts are correct, you can get more power up to the vehicles max advance from higher octane fuel. Higher octane fuel allows for certain gains in non-boosted conditions. It is also not limited to just compression ratio issues as it is only one of the controlling factors. Basically, cars with variable timming control can maintain higher power output (up to max) through a wider range of operation. There is a benefit. The only difference is the higher octane fuel will not give you more power then whatever the max power is for the car. It will just make sure you always get it.khamai said:Octane is a measurement that indicates how resistant the fuel is to predetonation = pinging. Typically the higher the compression the greater the demand for a higher octane number. Thus putting higher octane in an engine that requires 87 is pretty much a waste of money since you can't change the compression ratio on the fly. However, for engines with Turbos or Superchargers the ECU can potentially control the boost and raise it until reaching pre-detonation (pinging).