... This arrangement allows the engine to operate at a much higher compression ratio - a measure of the amount by which the fuel-air mixture is compressed before being ignited - than normal. As a result, an average car engine can be "downsized" to one that should have around 23 per cent better fuel efficiency, Ford says. ...
"higher compression ratio" means an entirely new engine. Running on 100% alcohol in the gas tank, as can be done in Brazil's flex fuel cars, requires only some minor changes to the gasoline only engine design and does slightly boost the HP, but lowers the range as alcohol has on 70% of the energy content of gasoline / gallon. Because more than 9 of evey 10 cars made in Brazil are now flex fuel, the larger production volume makes them LESS expensive to produce than the few gas-only models that are still made. (In the first model year, flex-fuel cost about $100 more.)
Ford's idea has promise for newly designed cars and with smaller motors (less weight)*. Thus there are significant other savings: As I recall, every pound you can remove from the engine is 8 pounds less total car weight. Why some engines are with aluminum blocks and steel sleve inserts for the pistons to run in etc. but just upping the % alcohol in the US gasoline supply will imediately reduce the flow or funds to countries supporting the terrorists, and can significantly reduce the cost of driving in the US if the 54cent/ gallon import duty on alcohol were removed. Less air pollution / global warming would be welcome side effects. The many benefits are so obvious that this anti-free trade tarriff would have been removed years ago if IOWA were not the first state to hold its primary election process.
In Brazil this percentage is government adjusted in effort to balance the suplies of gasoline and alcohol available. It goes as high as 25% alcohol in what comes form the "gasoline pump" at the service station, but that is about the limit if the car was designed for gas only. I think the percent alcohol in the gasoline is in the high teens now.
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*Separate injectors for both gas and alcohol, the extra fuel tank etc will surley add more than $100 to the cost, I would guess. Thus I see no advantage over a flex fuel car as it can certainly have the same, if not higher, compression ratio and reduced weight. As Ford liked to say in ads: "Ford has a better idea." but Brazil had a better one, 35 years ago with the high-compression, alcohol-only car!*
For several years Brazil has been making alcohol power small airplanes (Higher power with less weight and the maintance has turned out to be less also. They do not have the range of a gas powered plane, so mainly are used as crop dusters which need to return for more pesticide often anyway.)
PS to
hypewaders I bet you know already but for the benefit of others: Some WWII planes used water injecton to temporarily boost power. I think that works because the H2O droplets became steam as the piston went down to keep the force on it higher longer - offset some of the pressure reduction as the combustion gasses expanded.
I do not know why mixing gas and alcohol in the fuel is a "bad idea" - if it is it, it must be very easy to fix as cars in Brazil have been doing that for more than 30 years - As noted above when alcohol is in short supply little is added but just after the harvest there is 25% alcohol in the "gasoline" supplied in Brazil. There is no noticible problem. It should have appeared in 30+ years of doing this if it were real. Many people who owned "gas only" cars ran on their own mix at the pump - put some in from both the gas and the alcohol pumps. I owned a Russian made Lada (4 wheel drive) and it was Gas only. When alcohol was much cheaper I often did this, but it had significantly reduced power on a 50/50 mix. Russian gas is of low quality so I though I could safely mix at the pump. Perhaps the one time I made a 50/50 mix there was already 25% alcohol in the "gas"?
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*They used higher compression than is possible in the flex fuel cars, so cannot run on gasoline. They became very un popular when the price of surgar was high (20 or so cents / pound) as then most sugar cane processors made only sugar and it was very hard and expensive to get fuel for your alcohol only car for a couple of years.