happycamper515
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Anyone with the 2.0 NA engine running 91 octane gas? Was there a noticeable difference going from 87 to 91?
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I do use 89 E-Free, really seem to get slightly better ga$ mileages and takeoff than regular 87 & reg 89 (butt dyno, honestly.. no real data besides the ga$ mileages).Anyone with the 2.0 NA engine running 91 octane gas? Was there a noticeable difference going from 87 to 91?
NO, you won't notice a difference other then your wallet bieng lighter.Anyone with the 2.0 NA engine running 91 octane gas? Was there a noticeable difference going from 87 to 91?
And with good reason, Ethanol is less energy dense then gasoline (see the section about Fuel Properties) https://afdc.energy.gov/fuels/ethanol_fuel_basics.html so with Ethanol having 30% lower energy density and accounting for up to 10% of the fuel mix in regular gasoline you must mathematically get lower fuel mileage (probably not more then 3% if my math is accurate), based on simple science. The question becomes is the increase in fuel mileage enough to justify the added cost of Ethanol Free Gas, for me it's NOT. I generally only run (or ran) Ethanol Free in older Pre 2000's cars as the Ethanol loves to eat teh seals in older fuel systems, once ethanol mix fuels became the standard car manufactures changed up materials.Umm.. no
I do use 89 E-Free, really seem to get slightly better ga$ mileages and takeoff than regular 87 & reg 89 (butt dyno, honestly.. no real data besides the ga$ mileages).
exactly. premium fuel is not 'better' than regular. In absolute terms, it's actually worse. It retards combustion in order to avoid pre-ignition knock. But you will experience the enjoyment of paying more. Also ethanol does have a benefit; it dissolves into solution water and water-based contaminants so that they never accumulate at the bottom of your gas tank.NO, you won't notice a difference other then your wallet bieng lighter.
And with good reason, Ethanol is less energy dense then gasoline (see the section about Fuel Properties) https://afdc.energy.gov/fuels/ethanol_fuel_basics.html so with Ethanol having 30% lower energy density and accounting for up to 10% of the fuel mix in regular gasoline you must mathematically get lower fuel mileage (probably not more then 3% if my math is accurate), based on simple science. The question becomes is the increase in fuel mileage enough to justify the added cost of Ethanol Free Gas, for me it's NOT. I generally only run (or ran) Ethanol Free in older Pre 2000's cars as the Ethanol loves to eat teh seals in older fuel systems, once ethanol mix fuels became the standard car manufactures changed up materials.
If we are comparing octane with the same content ethanol (10%) in pump gas stations, you are half right. If a car is designed to run 93 from the factory, and you put 87 in, then timing is retarded because of excess misfires. Higher octane in a car that’s designed for low octane will not retard the flame front, it allows for higher potential maximum cylinder pressure, so you could either change compression ratio, timing, or add boost (very minuscule). The only downside to running 93 is more money, but comes with peace of mind. Remember I’m not talking about changing ethanol content. That’s an area I haven’t mastered yet since I’ve yet to experiment with e85, but soon to come I will.exactly. premium fuel is not 'better' than regular. In absolute terms, it's actually worse. It retards combustion in order to avoid pre-ignition knock. But you will experience the enjoyment of paying more. Also ethanol does have a benefit; it dissolves into solution water and water-based contaminants so that they never accumulate at the bottom of your gas tank.
I believe that the way premium allows for higher potential maximum cylinder pressure is by delaying ,in effect, combustion so that it doesn't take place before it's supposed to. This is accomplished by making the fuel-air mixture less combustible. In and of itself this does not make the fuel "more powerful", it only allows for higher compression in the chamber before combustion. It is this higher compression ratio which results in more horsepower being produced, not the fuel itself. Ounce for ounce regular gas packs more of a wallop than premium because it contains more potential energy. The additive in premium fuel reduces the potential energy produced. If you put regular into a car that calls for premium it ignites and combusts too early, before the spark plug fires , because of the greater heat and pressure in the combustion chamber. If you put premium into a car that calls for regular you accomplish absolutely nothing. Any increase in power that you think you feel is the placebo effect. Nor is there any increase in gas mileage.If we are comparing octane with the same content ethanol (10%) in pump gas stations, you are half right. If a car is designed to run 93 from the factory, and you put 87 in, then timing is retarded because of excess misfires. Higher octane in a car that’s designed for low octane will not retard the flame front, it allows for higher potential maximum cylinder pressure, so you could either change compression ratio, timing, or add boost (very minuscule). The only downside to running 93 is more money, but comes with peace of mind. Remember I’m not talking about changing ethanol content. That’s an area I haven’t mastered yet since I’ve yet to experiment with e85, but soon to come I will.