I donāt know for sure, but I heard the pumping setups are very expensive and a lot of gas stations donāt want to invest in setting their stations up for it.
I think it takes about 20% more E85 (less energy density) than gas to make the same power, which means fuel economy suffers. I don't think it could take over for gas unless it was 20% cheaper (which it isn't), also because it requires 20% more fuel there are more by products from combustion (CO2). So in some ways it doesn't make anyone happy (those wanting cheaper and those wanting greener). Anyways, I don't think the demand ever occured like many wanted. Little demand makes it hard for gas stations which have fairly low margins to begin with. I run it in my Mustang and I am very greatful for it as I think it's octane is 110 equivalent (works great with high compression boosted applications.
Yes you can run it without a tune and pick up a little bit of power too. Have a look here. A Flex tune allows you to run any combination of pump gas and E85.
According to Lund Racing tuner Alejandro Flores you can. He says thatās exactly what he did in his video above and ended up with E50+ ethanol when combined with pump gas and actually shaved off a couple of tenths in his 1/4 mile draggy test. There are even others on here, who have reported that they run E30 in their cars. Having said that, I would recommend a Flex tune to maximize any gains to be had from running E85.
I'm always open to being wrong and learning. That being said, I am Lund tuned (second car tuned by Lund), I run E85 consistently and I follow Alex regularly. I think there is 1 major variable here to what is going on with this truck. It is a flex truck from Ford. It has Flex logic from the factory. Notice the yellow ring around the filler neck. Thats why he can run on a "stock" tune. Right after he puts E in the tank he immediately watches for the learn flag to 0. And he says those very words. "So now you guys know how flex fuel works".
I wouldnāt do it on my car. I was just pointing out that some have done it successfully (mixed a few gallons of E85 with pump as). For those that do, I would never suggest putting in more than a few gallons. I too am Lund tuned on pump gas, Flex, E85R and nitrous and believe in leaving the tuning to the pros. I just pay to play. My car lives on the Flex tune 98% of the time.
I see what you are saying about low dilution ratios. Although I'm not sure what Lund would say about that(or what they technically could say
I dont know what the actual data is (both tune and power) on low level E dilution is, or how beneficial it actually is without a tune. I think the danger here is how "run E85" is defined. You can imagine that this throws it into a big sea of variables. Some people put 3 gallons on top of 13 and some would put 4 gallons on top of 4 gallons of gas. There is just a LARGE window of improper low level dilution possibilities which means if people dont educate themselves, it leaves open the possibility of engine damage.....IF there are truly any appreciable documentable advantage.