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great topic
Good posts, this is a hot-button issue of mine. I think Ethanol is getting a bad rap at the way it's being introduced. It's a flat different fuel than gasoline, same as diesel (from gas). I hate flex fuel engines because they get crappy gas mileage on ethanol. It'd be like making an engine to run on gas or kerosene, it might be OK on one, but it will always suck on the other. They're just different.
I was bummed in your first post when you installed a new engine. I was bummed you just installed a new engine rather than doing a rebuild or a custom build (I understand the cost problem though). Ethanol has amazingly high octane ratings, much like the leaded gas. For emissions our compression ratios have come way down from the 13:1 in '73 to a more 8-9.5:1 from then to now, though it is going back up. Since ethanol has 20% less power per same quantity of gas, when you run it, your computer simply pumps 20% more fuel into your engine (that's very simplified). This is where the fuel mileage reduction comes in, more intake means worse FE, and more exhaust means hotter manifold temps.
If you want to truly resolve the issue, you would need to build the engine to only run a specific version of ethanol, E85 is great for cooler climates, E100 doesn't start in the cold so they add gas which is much better for this. You would need a higher compression ratio to fully take advantage of the higher octane. An ethanol specific cam would be nice. But the main issue would be having a custom tune done (this is where carbs are nice for me).
Great points, you are fully hitting the bullseye on my problem with the flex fuel thing going on. Alternative fuels are just not gas. Ethanol is not a miracle fuel. But we need to get off gas, so whatever path we decide on I wish we'd just commit and go with it. The so-so approach on anything is not helping public perception, IMO.
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