Has Anyone done high compression e85 motors on a big boat?
01-28-2017, 04:50 PM
#42
Registered
Basically the more enrichment your boat needs to cruise and the total E content, the bigger the difference.
A light cat for example will see the least difference, but I big heavy blown V bottom the most. Again, I would put the range from 15-25% in reality
A light cat for example will see the least difference, but I big heavy blown V bottom the most. Again, I would put the range from 15-25% in reality
01-28-2017, 07:05 PM
#43
Registered
I personally don't have any E85 vehicles, but most I know who drive them say mileage difference isn't that bad on the highway. I bet on boosted EFI boats you could tune in some cruise efficiency due to the added power potential. That's the numbers I would want to see first.
01-28-2017, 11:42 PM
#44
Registered
Probably one of the biggest reasons you don't see more boats running E85 or high alcohol blends is the lack of ECU advancements. Beside the QC4v, the standard Merc ECU hasn't advanced much from the 90's. As mentioned above, to make this all work for the average Joe, the ECU requires a way to know exactly how much alcohol is in the fuel.
While aftermarket ECU's allow you to easily adjust fuel and timing mixtures, some by simply flipping a switch. Modern automotive ECU's have specific tables that adjust these mixtures based off the flex fuel sensor on the fly. These tables can be further refined by software like EFIlive [my favorite] or HP Tuners. So unless your running a flex fuel automotive ECU, you're stuck tuning the engine for a specific blend and sticking to it. No different than jetting a carb. For old school blower and carbs, straight methanol is the long time fail-safe choice.
For everyone considering running E85 in anything, I'd suggest owning the Quick Fuel E85 Fuel Testers available at Summit for under $20.
One other point that often gets overlooked, or misunderstood about alcohol fuels is the BTU and Oxygen content difference from gasoline. While alcohols have lower BTU values [requiring more fuel to achieve same heat], it also caries it's own oxygen molecules. Allowing more fuel to be stuffed in the cylinder and remain stoke. That's like running a shot of nitrous all the time. Why the power potential is always higher on alcohol blends. The Octane value is simply resistance to detonation, but it comes in to play with compression, boost pressures, and timing limits. Potential Power...
Below is the official ASTM BTU chart that breaks down common fuel values. At first glance Ethanol / Methanol looks like a big loser based on BTU's alone. But the truth is those extra attached oxygen molecules pay off big time in the combustion chamber. If that doesn't convince ya to check it out further, remember E85 burns cleaner, has lower emissions, and the majority of your fuel $ goes to midwest farmers vs middle east oil barons...
http://www.afdc.energy.gov/fuels/fue...ison_chart.pdf
While aftermarket ECU's allow you to easily adjust fuel and timing mixtures, some by simply flipping a switch. Modern automotive ECU's have specific tables that adjust these mixtures based off the flex fuel sensor on the fly. These tables can be further refined by software like EFIlive [my favorite] or HP Tuners. So unless your running a flex fuel automotive ECU, you're stuck tuning the engine for a specific blend and sticking to it. No different than jetting a carb. For old school blower and carbs, straight methanol is the long time fail-safe choice.
For everyone considering running E85 in anything, I'd suggest owning the Quick Fuel E85 Fuel Testers available at Summit for under $20.
One other point that often gets overlooked, or misunderstood about alcohol fuels is the BTU and Oxygen content difference from gasoline. While alcohols have lower BTU values [requiring more fuel to achieve same heat], it also caries it's own oxygen molecules. Allowing more fuel to be stuffed in the cylinder and remain stoke. That's like running a shot of nitrous all the time. Why the power potential is always higher on alcohol blends. The Octane value is simply resistance to detonation, but it comes in to play with compression, boost pressures, and timing limits. Potential Power...
Below is the official ASTM BTU chart that breaks down common fuel values. At first glance Ethanol / Methanol looks like a big loser based on BTU's alone. But the truth is those extra attached oxygen molecules pay off big time in the combustion chamber. If that doesn't convince ya to check it out further, remember E85 burns cleaner, has lower emissions, and the majority of your fuel $ goes to midwest farmers vs middle east oil barons...
http://www.afdc.energy.gov/fuels/fue...ison_chart.pdf
01-29-2017, 02:24 AM
#45
Registered
Depending on who you ask, you are probably correct Justfishing.
I spent past 10yrs involved in the biofuel industry. Registered producer of biodiesel, using mainly recycled "second use" feedstocks. Biodiesel energy in / energy out, and final emission numbers are actually far better than Ethanol. But half the BioD produced here gets shipped up to Canada where they have decent mandates to use it. About the only place I ever find 20% biodiesel in all the pumps is at Pilot.. So I got wise and bailed out early last year.
The whole US biofuel industry has been screwed up since day one. Our 15% Ethanol rule causes more mechanical problems than it's worth. Just enough alcohol tossed in there to attract water out of the air. Reason boaters love it.. lol. Plus as you stated the energy required to produce it is likely a wash. 3 energy units out for 1 input is the best est numbers they can muster from corn. Rest of the world uses sugar cane, which has about a 11 to 1 return. Corn alcohol is far better for drinking....
All that aside, long before I started making fuel I was heavy into making power. Methanol and Ethanol do that far better than gasoline. So for that reason alone I support running E85, or any blend that actually has a positive effect on performance. If you can be a little greener by maybe thinking outside the box then more power to ya. At least if you sink on E85 you'll kill less fish..
I spent past 10yrs involved in the biofuel industry. Registered producer of biodiesel, using mainly recycled "second use" feedstocks. Biodiesel energy in / energy out, and final emission numbers are actually far better than Ethanol. But half the BioD produced here gets shipped up to Canada where they have decent mandates to use it. About the only place I ever find 20% biodiesel in all the pumps is at Pilot.. So I got wise and bailed out early last year.
The whole US biofuel industry has been screwed up since day one. Our 15% Ethanol rule causes more mechanical problems than it's worth. Just enough alcohol tossed in there to attract water out of the air. Reason boaters love it.. lol. Plus as you stated the energy required to produce it is likely a wash. 3 energy units out for 1 input is the best est numbers they can muster from corn. Rest of the world uses sugar cane, which has about a 11 to 1 return. Corn alcohol is far better for drinking....
All that aside, long before I started making fuel I was heavy into making power. Methanol and Ethanol do that far better than gasoline. So for that reason alone I support running E85, or any blend that actually has a positive effect on performance. If you can be a little greener by maybe thinking outside the box then more power to ya. At least if you sink on E85 you'll kill less fish..
01-29-2017, 06:24 AM
#46
Registered
Yeah, you really need to turn the decision into a E85 vs race fuel decision. If you are setup to make all the power you can and 93 suffices, E probably not right for you. But, if you could make more power and 93 is the limiting factor for the current tune, E is the drug your parents warned you about.... they knew you would like it too much
01-29-2017, 08:05 AM
#47
Registered
we race with it...fantasic stuff for boosted apps, run 25psi w/ no intercooler on a LSX setup, works awesome and cheap. not available easily to run in a boat for us, in a NA motor you would need over 12-1 comp to see any benefit, fuel system must be able to handle 50% more volume, you burn about 40% in truth on a performance app.
