By Bob Reynolds, President of Downstream Alternatives Jay Leno's anti-ethanol rant (AW 3/2/15), aside from misrepresenting the facts, misses an opportunity to address the problem of low-quality replacement parts for vintage vehicle fuel systems. Leno states some companies don't use ethanol compatible materials when making replacement parts. Why not? Ethanol has been widely used in U.S. gasoline for over three decades. Today, over 95% of all U.S. gasoline contains 10% ethanol. Vintage car owners should demand compatible replacement parts. That is a far more reasonable approach than attempting to change all the gasoline to address a special segment of the market. Even if the Renewable Fuel Standard didn't exist refiners would still use ethanol because it is a low-priced source of clean octane, raising the octane of the fuel by nearly 3 numbers while lowering its production cost by up to 4 cents per gallon. I served for over three decades on the "ASTM International" committee that sets gasoline standards. All gasoline, with or without ethanol, must meet the same specifications including corrosion properties and oxidation stability (shelf life). Gasoline has undergone numerous compositional changes over the past century. Many times such changes have impacted some segment of the motoring public, often the vintage car owner. As an example, when lead was phased out of gasoline due to its severe health impacts, not only was octane reduced but the loss of lubricating effects of lead combustion products caused exhaust valve seat recession in engines with unhardened valve seats. Numerous tests have demonstrated which materials are compatible with ethanol. Unfortunately, tests are rarely done on materials on that are no longer used. One test did, however, look at ethanol use in vintage cars. In 2007 Hagerty Insurance (which insures many of our vintage cars) partnered with Kettering University's Advanced Engine Research Lab and tested ethanol blends in vintage cars ranging in age from 1940s to 1970s model years. Hagerty Magazine summarized that "after 1500 hours of testing...fuel lines didn't leak and fuel pumps did not fail" and concluded that "with minor updates and proper maintenance E10 will not prevent the ability to enjoy your collector car." Leno is correct that ethanol absorbs water. But, even in an open fuel system it would take months to absorb enough water to saturate an ethanol blend, which equates to about 4 teaspoons of water per gallon. By comparison gasoline can only absorb 0.15 teaspoons of water per gallon before the water starts to separate out, resulting in water on the bottom of the tank, which is far more corrosive than water in suspension. He is also correct that ethanol has a solvent effect, removing built up sludge and varnish in the fuel system that results from the use of the lower quality components commonly in use when such vintage cars were in common use. It should be noted that this is a one-time occurrence and once clean is not a problem. It should not clog fuel lines or carburetor jets if proper fuel filters are in place. Finally, I find it interesting that Leno seemed to be pro-ethanol (E85 Corvette) until he began plugging VP Racing Products (e.g., subject article, YouTube etc.) which markets ethanol-free fuels and ethanol-related additives.