Ford Mustang Boss 429: $550,000
The mythical Mustang Boss 429 is a proper muscle car legend. Ford conceived it in 1969 as a pure racing engine intended for use in NASCAR championships. The Boss 429 featured a totally different engine architecture than the rest of Ford’s big blocks. They made the Boss 429 much wider. It also had semi-Hemi combustion chambers that helped achieve higher revs, better flow inside the head. Ultimately, it produced more power and torque.
With factory ratings of 375 HP, this unit produced over 500 HP, but it created much more in race trim. Ford decided to put this engine into the Mustang, offering a limited production Boss 429. However, NASCAR decided not to homologate it since they only accepted intermediate and full-size cars, but the Mustang was a pony car. So, Ford homologated the Torino Talladega as the body and the Boss 429 as the engine. It participated in the 1969 season with Torinos and Mercury Cyclones powered by Boss 429 engines.
Those cars proved successful, winning 30 out of 54 races that year. The secret was the engine. They designed the Boss 429 to run at high RPMs for long periods of time to achieve its peak power high in the RPM range. That is why the Mustang Boss 429 never fulfilled its street racing potential. Its mighty engine needed long superspeedway tracks to show its true power, rather than short quarter-mile stretches.
Available only in 1969 and 1970 as an engine option on a Mustang Sportsroof, they only produced 1,300 Boss 429s. This is a highly sought after model in present years. The Boss 429 that sold for a whopping $550,000 in 2013 was an unbelievably preserved example. It was in its original condition and with only approximately 1,000 miles on the clock. The time machine condition justified the enormous price, but many restored Boss 429s Mustangs also command high prices.