last two weeks been getting 24.5 to 25 driving very nicely back / forth to work on the highway with only one stop sign. (at the end of my street!). Checked with a calculator and at the pump not the trip thingy. I am runnig the premium Diablo tune but fill with 89 octane. Now I benefit from the added spark advance and fuel curves but I don't floor it since there's a gas crisis. With dual knock sensors (and my good "sense") I will not damage the engine from pre-ignition. i haver built many engine and have 3 supercharged cars so no fear of damage here. NOTE:You will get the best utility from the lowest octane fuel too. Only use High Octane if you have too as it retards combustion.
BTW is is 281 cubic inches... not 305.
BTW is is 281 cubic inches... not 305.
