Does anybody or has anybody used E85 because the octane rating is higher. I know the carb would have to rejetted or the ECM remapped, but it seems like the benifits outweigh the negatives IF and ONLY IF you were very carefull about removing any water from your tank and your fuel system was compatable with it.

a good question

Not so sure it is worth it. In the automotive industry, manufacturers say that you will loose 20-30% fuel economy. I dont know how this will transfer over to the marine industry. It seems like a lot of effort and money for little or no return. I'm gonna pass on the idea.

...if your measure of return is fuel economy.

It depends on how high of an octaine rateing you need. E85 has an octain rateing of 96.

People are certainly experimenting with it in automotive applications. Octane for E85 is somewhere north of 100, maybe 105 or so? Optimizing an engine for this will certainly result in power gains over premium gasoline, while not forcing you to run "race" fuel at $6+/gal.

The fuel contains less energy per lb, so you will burn more in the process. The price of e85 compared to gasoline (its cheaper) reflects this reduced energy value.

It's definitely possible, it will work, but it won't be easy to keep the fuel quality high in a boat. For a boat that spends most of it's life on a trailer, it may be a matter of not storing fuel in the boat, always refilling with fresh fuel before an outing.


This of course doesn't in any way address the political mess that is ethanol and the ridiculous notion that its a good idea to turn food into fuel on a large scale. It's simply not sustainable and will hopefully come to an end sooner than later. Until we solve the world's food supply issues, we ought to be looking elsewhere for fuel.

Which doesn't rule out ethanol, but only ethanol produced from food crops.

Reducing Oil Consumption Is The Goal, Edelbrock Just Came Out With A Carb To Convert To E85, Any Engine Builders With Input?

Tuned properly, I think it would be a much lower cost alternative to race fuel at $8-10 a gallon. Even if it would take 50% more of the E85 to make the same power, the cost would still be much lower. The biggest neagative I can see is current availabilty. Until Merc makes a flex fuel engine, I can't see it being available on the water.

Octane alone will not increase power. You'll need a higher compression ratio, or more blower boost to take advantage of the additional octane in the form of a power increase.

The other question mark is whether the ethanol will absorb too much water in a marine environment. It would probably not be a good idea for a boat that sits near or on the water.

Having said this, it would make an interesting experiment, and I would like to hear the results.

Michael