First a little about gas.
Because higher octane gas has less energy (lighter density) it actually gets LESS miles per gallon...but more performance...
Shorter hydrocarbon strands for the lighter, and longer for the denser. Gasoline is a regulated mix of hydrocarbon types, in order to burn within a certain specification.
Second, almost all gas is the same, it comes from the same refinery, is loaded into a tanker truck at the same place, and contains the same mix of distillates. The only major difference is a quart can of detergent added to the tanker truck. (5000+ gallons)
Smart says use 95 RON (Research Octane Number). This translates to 90-91 AKI (Anti Knock Index), or (Research+Motor octane)/2), or the number on the gas pump.
91 RON, the minimum Smarts will use, is 87 AKI.
I have use all three grades, regular, mid, and super; and have found that regular gives me the roughest idle, but the best mileage over long highway trips, and 92-93 AKI gives me great power, but poor MPG.
I am splitting the difference and putting in 89, and adding 16 ounces ethanol (E85) to five gallons, or 32 oz (quart) to ten gallons, to boost the octane.
This adds about 2.5% (actually a little less, only 70 to 85% ethanol in E85), and most gas has between 6.9 (Federal minimum) and 10%.
Gripe all you want about ethanol, there is a lot WORSE we could add to boost octane, tetra-ethyl lead (major air polluter), methyl tert-butyl ether (major water polluter), and benzene (cancer).
Ethanol is also an oxygenated fuel, so less tailpipe emissions.
Does this help clear up a few things?
Because higher octane gas has less energy (lighter density) it actually gets LESS miles per gallon...but more performance...
Shorter hydrocarbon strands for the lighter, and longer for the denser. Gasoline is a regulated mix of hydrocarbon types, in order to burn within a certain specification.
Second, almost all gas is the same, it comes from the same refinery, is loaded into a tanker truck at the same place, and contains the same mix of distillates. The only major difference is a quart can of detergent added to the tanker truck. (5000+ gallons)
Smart says use 95 RON (Research Octane Number). This translates to 90-91 AKI (Anti Knock Index), or (Research+Motor octane)/2), or the number on the gas pump.
91 RON, the minimum Smarts will use, is 87 AKI.
I have use all three grades, regular, mid, and super; and have found that regular gives me the roughest idle, but the best mileage over long highway trips, and 92-93 AKI gives me great power, but poor MPG.
I am splitting the difference and putting in 89, and adding 16 ounces ethanol (E85) to five gallons, or 32 oz (quart) to ten gallons, to boost the octane.
This adds about 2.5% (actually a little less, only 70 to 85% ethanol in E85), and most gas has between 6.9 (Federal minimum) and 10%.
Gripe all you want about ethanol, there is a lot WORSE we could add to boost octane, tetra-ethyl lead (major air polluter), methyl tert-butyl ether (major water polluter), and benzene (cancer).
Ethanol is also an oxygenated fuel, so less tailpipe emissions.
Does this help clear up a few things?