Reading comprehension is questionable, but how I understand it is the kinetic wants to light off the gas with a higher compression so the octane is more a pressure valve, a fuse with some time on it. With the race gas, the burn rate is faster so it needs a higher octane to keep it from lighting off under heavy load-low rpm = Knock/Pre-ign... ask me how I know?
lower octane higher burn rate makes more push in lower compression engines.( burns faster, piston at top of stroke)
higher octane lower burn rate makes less power in lower compression engines. ( burns slower, chases piston down the stroke)
From VP Q&A: "As with Q16, so far I have left the timing alone. Run what timing you had with regular methanol. Here’s my thought. The hydrocarbons in the fuel help vaporization, so you SHOULD be able to retard the timing a bit. But the fuel also contains nitroparrifins, which generally need the timing advanced to start the burn earlier. Since they are both in the fuel, they almost seem to cancel each other out, hence the timing will stay the same. Weird huh?"
lower octane in high compression engine will pre ignite causing "piston damage ( spark knock)
Correct. Here is the ask me how I know; was going uphill in a lower rpm with regular gas [87], heard the multi-knock before I had a chance to unload. Pulled a plug and where they have a V in the center of the piston dome for the lathe, the scope saw the moon crater as the V is no longer, but has tiny welded aluminum balls around the crater, and gray dots vaporized into the porcelain nose of the spark plug. So for the plug to catch that dot that close, it would seem knock happens there, or a millisecond before TDC.
So the secret to get away with running the lowest octane is to not load the engine at lower rpms. That one knock is fast enough to melt aluminum... remember.
higher octane in high compression engine will burn slower allowing use of higher compression to make more power
Again, not the fastest molecule in the gas, but my understanding is that you need a higher octane, because you want the mix to wait, because it burns faster.
I'm going to explain the current king of the drag strip or don't show up without kind of high performance bike. They found out that running 87 at the strip is better than race gas. So my guess is, you take two of the same bike [all stock] and one runs race, the other runs regular.
The next way to think is see if more air(?) is not it for more HP, but the same 14.7 psi gulp when the intake valve closes. So with the same fuel-to-air is the same, it's a speed(!)event, meaning, who did what faster? Therefore, you can see that the lower octane fired off sooner = Faster is whom? I'll backup the theory about a speed event v. more. Same intake port length and cc is the equal volume. One port has a slight C-curve to it and the other is l-straight. Who drags more around a corner and who is faster if the curve is straight. The friction is who moves faster? Get it, it's not a more-theory, but a 'speed-event' = More HP.
Make sense seeing the difference between saying More v. A Speed Event(s) =Gains 'more' HP?
a. I smoothed the port so the friction makes it flow faster is the same gulp into the chamber.
b. I run a faster fire off to speed up the event is less octane used, same volume of gas pulled from said jet holes.
c. I see said the Alpha number used for BACKUP = 14.7 Pee Yes I am sticking with this theory and you can have your reality... Good luck chasing a trophy... I'd be taking that from you is my reality.
Signed,
NOLTT (Nasty Over Lapper Trophy Taker) I wish. YOu can't take the line out of me or the race face. Make sense? My interpreter will be here if the hand went over the head.
