How much of a difference of power will different Octanes of fuel give

Hey guys, not sure if this has been asked before, but I could not find anything in the forums from searching.

Does anyone know how much of a difference you'd expect to see from a tune on RON 97 and RON 100? I'm thinking of going back to my tuner for a re-tune, but due to the current fuel prices I'm considering dropping down to a lower octane just to save some $$$ on fuel costs.

So I would like know how much of a loss in potential HP would i be seeing if I were to tune on a lower octane fuel? Please share your experiences.

Thanks

 

RON100 =95.5 RON97=93 for those in north America.

Lots of us in north America are running RON96 (91) or RON98 (94) and there's some power difference sure I myself have two tunes for one for each of the above ratings I don't know the last time a actually compared numbers can't find old vdyno either, but Dyno tells you a difference. Real question is what % ethanol do your mixes have at the pump because if there's a difference that's where you'll really see it.

Other question is how long will it take you to make up the difference for the cost of a tune

 

Octane is resistance to knock. If you're tuning for a lower octane you're going to be removing timing to reduce the chance of knock or detonation. Any time you remove timing you're losing power.

Where I live some stations have 91 and others have 93. I notice no difference in my car using either octane.

If you're worried about fuel costs and driving a Speed then it isn't the car to be fuel conservative with. They don't get horrible mileage but it isn't a Civic or Corolla. If you beat on the car constantly you'll go through tons of fuel. If you drive like a respectable driver and know that with great power comes great responsibility then you'll save fuel that way.