Is there any benefit in running higher grade gasoline in an outboard engine. Improved gas mileage or anything?

BOTH IMPROVE GAS AND LESS ETHINALE.

run what the manufacturer recommends no need to waste money on higher octane. if your wanting to get.better performance buy some ethanol free. I have been running it in my last 2 boats and it.seams to go a lot further

l.

I only use mid grade because it is proven that regular is not consistent on the percentage of ethanol because to have non-ethanol some has to be added somewhere else. The places to get non-ethanol is getting hard to find. We have seen up to 35% ethanol in regular.

I'm in the fuel equipment business, obviously there's some confused people out there.

"Midgrade" is blended at the pump from regular and premium, you don't go to the refinery and get a transport load of midgrade. If the regular is junk, midgrade is half junk.

There is no less ethanol in premium than regular, it's 10% which is dictated by the state for all unlead gas. I hate moonshine in my fuel, it just makes everything run like garbage.

ethanol actually adds performance to the fuel due to its higher octane levels, rated at 113 octane, ethanol is the highest rated performance fuel on the market

I always run mid grade in my outboard if it sits long enough losing 2 points of octane does not matter it would still be 87. The second reason is in my specific outboard the electronic timing module can cause detonation with 89 it has never happened. There is no magic fuel in stock configured outboard to increase HP. Personally I have never noticed any preformance difference between non ethanol and blended. Ragged edge preformance 1 or 2 MPH more can only be measured by guages not any noticable difference. I have never had ethanol degrade any fuel lines either the sun over time has destroyed a few bulbs and fuel lines mine is exposed when it starts to feel stiff I change it out. At 5 mpg in the sweet spot and 3 at wot does an extra mile per gallon matter I say no. It's dam expensive to run a V6 outboard period 2 or 4 stroke makes no difference they all get about the same MPG.

89 is my thing.

I have never run anything but regular gas, in fact some outboard manufacturers recommend not running higher octane.

Alcohol of any kind has a BTU of 7000 perlb whereas gasoline has 13,300 BTU's per pound. Gasoline will make more power than the blend so gas mileage will increase. The reason you run higher octane rating is to prevent preignition or detonation as some call it. If you have increased compression, more timing advance or any other factor that requires it then run the higher octane. If you are running a stock motor set up to factory specs it is a waste to run higher octane fuel. The wives tales run rampant on this but if you take the time to research it for yourself you will know. Pat is dead on with the midgrade and ethanol content.

Don't waste your money on higher octane fuel than your motor needs. It won't help and possible can be detrimental. Use the fuel grade recommended by the manufacturer. Jimmy P. Is right on.

The higher the octane rating, the slower and cooler the flame front of the combusted air/fuel mixture is. This is to help control pre-ignition / detonation in high compression engined with more ignition advance than a lower compression engine. Using high octane fuel in an engine that does not need it may actually increase carbon deposits.

Scott

I wish premium non ethanol was closer to me, got to use high grade due to engine mods.

I always add ethanol treatment to my boat fuel. I'm not certain it helps but have heard a lot of people recommend it.

My '01 Johnson 115 is recommended to use at least 89 octane. I have run it with the 89 octane and with 87 octane. I honestly could not tell a difference in power, top end, idle, or anything. I think so long as you aren't getting pre-ignition you don't need to go to a higher octane.

It is Hop but really expensive. Its call 100 octane aviation fuel. Has anyone else started putting fuel in and get a big whiff of propane?

lol, wish there was an airport close, I would fill the boat one time just to see what it would do.

I can go to winnsboro for non ethanol but dam its about 50 miles round trip. there is good gas (but with corn squeezins) just down the road at the station in alba, they go through a bunch of gas so it is always pretty fresh.
nuttin is cheap when the word boat is involved.

Hop, doesn't Star Mart still sell ethanol free?