No, just there is more volume to the exhaust flow. The flame front is a bit quicker than gas, so the timing between it and race gas will be similar. The burn is cooler though. So with a cooler charge AND higher octane, you are able to push it further without detonation. It keeps the combustion chamber a bit cooler resulting in less chance of the engine detonating when you push the timing and the boost (if a forced induction motor) further than you do with gas. I do believe that the higher exhaust volume does help spool a turbo a bit faster though. I noticed a bit faster spool at similar timing and actually had to reduce wastegate duty cycles to avoid going past the target boost point.