what about this?
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The only thing that guy got right was the part that higher octane ratings correlating to higher resistance to detonation. The parts claiming higher octane rating gasoline leaves more carbon deposits and higher octane gas having less power output potential leaves some room for clarification. I"m not a chemical engineer, but my understanding is that a gallon of 87 and 91 octane gas theoretically produces the same amount of energy when ignited. The only difference is the amount of pressure needed to ignite each type of fuel. Now, diesel on the other hand, I can understand. It takes much more compression before diesel will ignite compared to unleaded gasoline. However, the amount of energy dissipated by equal amounts of diesel and gasoline burned is not equal.
-Soren
-Soren
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just my opinion, but...
Who cares what the energy content of the fuel is. Power output is a matter of tuning.
You will make higher HP and torque # when propperly tuned for higher octane than if you tuned for lower octane. Because you can run more timing advance without knocking. You can still run a high compression engine on lower octane gas, but only if you tune the timing and AFR for that fuel. This won't be efficient though.
Ash
Who cares what the energy content of the fuel is. Power output is a matter of tuning.
You will make higher HP and torque # when propperly tuned for higher octane than if you tuned for lower octane. Because you can run more timing advance without knocking. You can still run a high compression engine on lower octane gas, but only if you tune the timing and AFR for that fuel. This won't be efficient though.
Ash
Originally posted by AzN121184
4. Using high octane fuel on an engine that doesn't require it can actually create an engine that's an "octane junkie". The cooler burning high-octane fuel can leave carbon deposits, that effectively change your compression and create hot-spots in your cylinders. This increases detonation, and requires the high-octane fuel to prevent it.
4. Using high octane fuel on an engine that doesn't require it can actually create an engine that's an "octane junkie". The cooler burning high-octane fuel can leave carbon deposits, that effectively change your compression and create hot-spots in your cylinders. This increases detonation, and requires the high-octane fuel to prevent it.
Um... that seems like a contradiction to me...
-Gagan