Why Was the Rotary Engine Banned from Racing?
2 Answers
Here are the reasons why the rotary engine was banned from racing: High fuel consumption and pollution emissions: Although the rotary engine has a higher power output than reciprocating piston engines, its lower compression ratio prevents the combustible air-fuel mixture from burning fully. As a result, the rotary engine cannot guarantee fuel efficiency or low emissions. Shorter engine lifespan: Due to the structural limitations of the rotary engine, the chambers are sealed by apex seals. Under high-speed operation, the contact surfaces between the apex seals and the chambers constantly change, leading to issues like gas leakage and blow-by. Additionally, the lubrication conditions between the apex seals and chambers are extremely poor, resulting in a shorter operational lifespan for the rotary engine. Automaker profitability concerns: At the time, automakers had already invested heavily in developing reciprocating piston engines, which had significant research and development potential. Switching to the rotary engine, which had uncertain prospects and issues like high fuel consumption, emissions, and a shorter lifespan, would not provide a clear return on investment.
Speaking of the ban on rotary engines in motorsports, it all started with Mazda's 787B victory at Le Mans in 1991. At that time, the rotary engine was compact yet powerful, squeezing out 700 horsepower from just 2.6 liters of displacement, outperforming even the 6-liter V12 engines on the same track. The race organizers saw this as unfair and immediately introduced new rules requiring all engines to be derived from production cars. The inherent advantages of the rotary engine became its downfall here—it disrupted the fair competition that motorsports strive for, akin to pitting an elementary school student against a professional boxer. Coupled with poor fuel economy and rapid wear, this unique structure ultimately couldn't escape the fate of being banned.
