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Old 08-23-2013, 03:44 AM   #89 (permalink)
It's all about Diesel
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Originally Posted by freebeard View Post
Your discussion of tuning for multi-fuels is interesting. What I tell teenagers operating gas pumps is that drag racers proved in the 1950s that pure alcohol is a great fuel, as is gasoline; but blending the two isn't efficient unless the carb jetting (shows my age) and compression ratio can vary on the fly. What do you think of‎? Generically it is a 'top-end oil'. Would that make the corn blend more palatable in a magnesium-cased flat four?
Compression varying on-the fly wouldn't be bad, altough not really essential. With direct injection available in newer engines, the knockings while running on gasoline at higher compression ratios can be suppressed more efficiently.

Regarding the Beetle engine, I've never used that Marvel Mystery Oil, but the engine itself can handle the ethanol blends easily. But if you would consider pure ethanol, a dual-carburettor setup with shorter intake manifolds for each cylinder bank is better since it's less prone to freeze, and idling stability is enhanced. Unless you would get an MPFI setup for it
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