Honda has made a number of naturally-aspirated V12 engines designed for Formula One motor racing; starting with the 1.5-litre RA271E engine in 1964, and ending with the 3.0-litre RA273E in 1968. This would be followed by a 21-year hiatus, until Honda reintroduced the new 3.5-litre RA121E in 1991. The RA121E would go down as the last V12 engine to win a Formula One World Championship. Honda's last-ever V12 engine, the RA122E/B, raced in 1992.