10 Rarest American Muscle Cars Ever Made

Most uncommon American muscle cars ever manufactured

After Plymouth’s successful Roadrunner line, the Plymouth Hemi Superbird was produced as a highly modified version in 1970. With its high-mounted, wing-like spoiler, fitted with a 426 cubic inch Hemi engine and many MOPAR high performance parts, this car was built purposely for racing. What’s probably most characteristic about it is its unique horn, whose sound mimics the sound of Looney Tunes’ Roadrunner.