What octane are you using ?

[DaddyRabbit]

Guys, if you'll indulge me for a moment. I have always heard from pro engine builders alike that higher octane = less power. The octane content of gasoline is there to control detonation. Higher octane only = more power when it is being utilized to control detonation from higher compression, advanced timing, etc.. So my thinking is you're shooting yourself in the foot w/high octane applications on stock equipment.

 

[mattmc2003]

Higher octane doesn't make more power, or less power. It just supports more power.

 

[windthrown]

Guys, if you'll indulge me for a moment. I have always heard from pro engine builders alike that higher octane = less power. The octane content of gasoline is there to control detonation. Higher octane only = more power when it is being utilized to control detonation from higher compression, advanced timing, etc.. So my thinking is you're shooting yourself in the foot w/high octane applications on stock equipment.

Higher octane has a tad more energy, typically. If it is all gas. And if you have your engine tuned for it with earlier ignition timing and higher compression, as you say. In an engine timed for regular gas, high octane gas is a waste, yes. You will not get any more power or performance out of it. I do not use anything other than regular in my 4-stroke lawn movers, tiller, and PU truck.

In the case of chainsaws, blowers and small 2-stroke engines, most are designed and tuned for mid-grade gas. The uneven burning of regular is going to lead to more fouling and carbon buildup. I use super in my 2-strokes mainly because the octane drops in gas with time at the pump and when being stored in the small gas tanks. And more even burning is a good thing in a small engine. No more power, but better engine life from less carbon buildup. No loss of power really, just not able to take advantage of the properties of more even burning for more potential power.