Two different types of Top Alcohol Dragster. Above, T/A injected dragster of Krister Johansson from Sweden; below, the supercharged methanol-burning car of Germany's Dennis Habermann.
Top Alcohol refers to two different classes in professional drag racing: Top Alcohol Dragster and the Top Alcohol Funny Car. Commonly known as "alky" cars, both are akin in design to the premier Top Fuel classes, but less powerful (about 3,500 bhp (2,600 kW; 3,500 PS)). In Top Alcohol Dragster, two types of engines are used: supercharged ("blown") alcohol (methanol)-burning engines or injectednitromethane-burning engines (called "A-Fuelers"; nitromethane is commonly called "fuel"). The Top Alcohol Funny Cars look similar to Top Fuel Funny Cars, but also with about half the power of a Top Fuel car. In this class only alcohol cars with three-speed transmissions are allowed.
Top Alcohol was devised in the 1970s as a replacement for the Top Gas class, which was similar but burned gasoline. Initially, alcohol dragsters competed against Funny Cars in a category known as Pro Comp, before a separate class of Top Alcohol Funny Car was created in the 1980s. It was within IHRA's version of this class use of ethanol fuel was pioneered with great success by Mark Thomas, an Ohio farmer who became a five-time champion within that organization. Despite this, ethanol has failed to capture the imagination of racers; the majority opt for more traditional methanol. Today both the Top Alcohol Dragster and Top Alcohol Funny Car compete in NHRA drag racing. They are classed not as professional but as sportsman. Top Alcohol classes also compete outside of North America, most notably in Australia and Europe. In Europe they are called Top Methanol Dragsters and Top Methanol Funny Cars.