Re: Shell's 100-RON fuel - what actually is it?

> How can alcohol "increase engine power?"  It can't. Either the engine is
> optimized for alcohol (and yes, you can extract a great deal of power
> from engines that use alcohol as fuel) or an engine is NOT optimized to
> burn alcohol. There's no direct comparison without changing the fuel
> system and compression ratio.
>
> Now if you do allow changing the fuel system, how do you compare?
> Probably the best way is on engine size. For any given engine
> displacement, setting it up to burn gasoline will net more horsepower
> out of the engine since more chemical energy can be pulled into the
> engine in the form of air/fuel mixture because the energy density of
> gasoline is higher. Its arguable that in the case of turbocharged or
> supercharged engines, you could run more boost with alcohol and
> therefore extract more power, but that is tantamount to simply
> increasing engine displacement anyway.

 In the late 1970s and early 1980s the USAC cars were putting out 1000+
bhp out of the 166 CID Turbo Offy. On gasoline it is doubtful much more
than 200-250 hp would have been possible.

 Alcohols allow radically more power to be produced in certain cases
because of alcohols' higher octane rating, and also the alcohol fuelled
engines can be run very rich which allows the alcohol to act as a
cooling medium.

 The 1952 GM LeSabre show car used a clean-sheet-of-paper engine which
was dual-fuel, but not in the sense of the current FFVs. It had a
gasoline carburetor used for starting and cruising and a methanol one
which opened progressively at high power.