Boss 429 Mustang

 If you’re a fan of the #3 Mustang on our list of all-time greats, you can thank…Mopar??? *Gasp* Truth is there is plenty of credit to go around for the 1969 Boss 429 Mustang, but the impetus for the legendary “Boss 9”  was Chrysler’s 426 HEMI engine. Ford was looking to develop a hemispherical engine