13. Ford Boss 429
The mythical Boss 429 engine is a proper muscle car legend. Ford built the engine in 1969 as a pure racing engine for use in the NASCAR championship. The Boss 429 featured different engine architecture than the rest of the Ford big blocks. The Boss 429 was much wider and had semi-Hemi combustion chambers that helped it achieve higher revs. With better flow inside the head, it produced more power and torque. Although it was factory-rated at 375 HP, in reality, this unit produced over 500 HP, and even more in race trim.
Ford decided to put the Boss 429 engine into the Mustang, creating a limited production Boss 429. However, NASCAR decided not to homologate it since the series only accepted intermediate and full-size cars and the Mustang was a pony car model. So, Ford homologated the Torino Talladega, adding the Boss 429. Ford participated in the 1969 season with Torinos and Mercury Cyclones powered with the Boss 429 engine. Those cars proved successful, winning 30 out of 54 races that year. Ford designed the Boss 429 to run at high RPMs for long periods of time and achieve peak power high in the rpm range. Unfortunately, the Mustang Boss 429 never fulfilled its street racing potential since the mighty engine needed those long superspeedway tracks to reach full power rather than short quarter-mile stretches.