best gas?

[baitmaster]

So a few yrs ago, I had a complete rebuild done on the 150. Mechanic said to run Premium gas. So I have, but our gas has up to 10% ethanol in it. Recently found a station that sells real gas (no corn), and it seems to run even better. Is this my imagination, or is it really running better? I know about the ethanol probs, (moisture, corrosion, plastic and rubber eater, etc. I have to haul gas in cans across town in order to get this good stuff, but it seems to be worth doing. It is from a cut rate station, so no additives like the major brands, should I add something to it?

 

[Cofe]

Re: best gas?

Real gas without ethanol, has more Btu's than a ethanol blend. In short, you will get a bigger bang in the cylinders thus better performance, and gas mileage. Permium has a higher octane content which will make the bang even bigger.
I search out for real unleaded gas stations when I can. Even for vehicles...

 

[JB]

Re: best gas?

Burning "premium" gas in an outboard is a waste of money and shortens the life of the engine. Calling higher octane gas "premium" and pretending it is somehow better quality than "regular" is the biggest lie ever.

High octane is needed in high compression 4 stroke engines to prevent preignition and detonation. A few highly modified 2 strokes might use it, but they are racing engines and usually burn exotic fuels, not including gasoline. They are usually alcohol based.

 

[cdn-pk]

Re: best gas?

not to offend any experienced people on this site, i have notice a difference as well. not just in my outboard but my lawn tractor too. i used it solely in my 1977 140 and in my 1986 120. so i'll keep using the premium. i have also seen some stabil additive made for ethanol blended gas and marine applications. read a few people around hear recommend it when using the blended gas

 

[JB]

Re: best gas?

Do what makes you feel good, cdn-pk. Just keep her decarbed. Glad you can afford it.

As for StaBil for ethanol or Marine StaBil I do recommend it. It isn't really necessary if routine maintenance is kept up, but that routine maintenance goes beyond what we used to do years ago. You now need a good water seperating fuel filter that is regularly serviced and you don't want to leave many gallons of E-10 sitting in your tank for months.

 

[baitmaster]

Re: best gas?

How does using Prem gas shorten the life of an engine? If my motor runs better on prem than reg, wouldnt it be the opposite? I think I have also read that higher octane fuels will store longer than lower octane fuels. Using the real gas in my old 390 (not stock) Ford truck will make the tires light up better than the corn gas too. Its also cheaper, but as I said, prob has no additives like Techron or Shell Nitrogen.

 

[hidef]

Re: best gas?

Higher octane does not relate to higher performance. Octane is a combustion inhibitor the higher the octane the harder it is to ignite the gasoline. If you have an engine that is prone to knocking and pinging on regular gas than switching to premium will help prevent it. High performance engines that require premium often have increased compression ratios, wild timing and sometimes forced induction. Burning premium a 4 stroke engine not designed for it will not do any harm other than cost you more money at the pump.

None of which applies to a consumer two stroke outboard with a carb. What premium will do in a two stroke is raise the cylinder temps which can cause the engine to fail.

 

[kenmyfam]

Re: best gas?

Burning "premium" gas in an outboard is a waste of money and shortens the life of the engine. Calling higher octane gas "premium" and pretending it is somehow better quality than "regular" is the biggest lie ever.

High octane is needed in high compression 4 stroke engines to prevent preignition and detonation. A few highly modified 2 strokes might use it, but they are racing engines and usually burn exotic fuels, not including gasoline. They are usually alcohol based.

I whole heartedly agree with this response.

 

[cfauvel]

Re: best gas?

not to offend any experienced people on this site, i have notice a difference as well. not just in my outboard but my lawn tractor too. i used it solely in my 1977 140 and in my 1986 120. so i'll keep using the premium. i have also seen some stabil additive made for ethanol blended gas and marine applications. read a few people around hear recommend it when using the blended gas

I think JB is right, it is not the extra octane that is making you feel performance gain it is the lack of ethanol. It is unfortunate for your pocket book that the non-ethanol fuel is premium, cuz, non-ethanol 87 octane would be just fine.

 

[cdn-pk]

Re: best gas?

no ethanol is why i use premium. i never understood why anyone would take away part of our food supply (corn) to produce ethanol. (seems like a great way to drive up the cost of both!)

cheers

 

[Jim311]

Re: best gas?

Premium fuel is usually designed for higher compression engines but it's not like you're going to damage anything running it. If you can find fuel without ethanol it will have more power and better fuel economy since ethanol has fewer BTUs than the gasoline it is replacing.

 

[cfauvel]

Re: best gas?

no ethanol is why i use premium. i never understood why anyone would take away part of our food supply (corn) to produce ethanol. (seems like a great way to drive up the cost of both!)

cheers

Right but the two are mutual exclusive, meaning that just because it is premium doesn't mean it is ethanol free.
More than likely where you are buyng gas , they are offering non-ethanol fuel at the premium grade, to make more money of course. If they offered regular gas with no ethanol, that would be cheaper than the premium, softer on the wallet and still feel the performance gain.

 

[JB]

Re: best gas?

The octane in non-alcohol gas is boosted with additives that are not friendly to 2 stroke engines. They leave deposits that shorten engine life. Decarb can help with this, but not solve it completely.

Try this, cfauvel: Alcohol is a renewable, cleaner burning energy source that we do not import from people who want to kill us.

 

[Cofe]

Re: best gas?

The octane in non-alcohol gas is boosted with additives that are not friendly to 2 stroke engines. They leave deposits that shorten engine life. Decarb can help with this, but not solve it completely.

Try this, cfauvel: Alcohol is a renewable, cleaner burning energy source that we do not import from people who want to kill us.

I would like to reply to that JB, but that involves politics. I will take a deep breath, and keep my dander down.

 

[wilde1j]

Re: best gas?

Ethanol has less energy per gallon than gasoline (which is why gas mileage sucks), is costing us taxpayers billions in price supports and blending fees, is hygroscopic (attracts water vapor), is a net engery loser when the energy to produce it is compared to what comes out and has caused the worldwide price of food to increase a lot. Other than that, it's a wonderful fuel. For me, I buy only ethanol free gas, when I can, since it's sold locally in one gas station and all marinas around here.

 

[cfauvel]

Re: best gas?

Try this, cfauvel: Alcohol is a renewable, cleaner burning energy source that we do not import from people who want to kill us.

Fiscally it doesn't make sense to use ethanol in our gas, as Wilde1J has stated. Part of our deficit are subsidies to ethanol producers. The 10% savings of gas in E10 is offset by the inefficiency it contributes. Maybe if an engine was designed to run ethanol from the ground up it would be a different story, I'm thinking of Formula One race cars, they can increase the compression ratio considerable and thus offset the lack of BTUs in the alcohol. I'd like to see some numbers on cars designed for E85.

 

[JB]

Re: best gas?

Should have kept my keyboard shut. Too many political comments to edit, so. . .end of thread.