Story
1973 Plymouth Road Runner 440
The strongest 1973 Road Runner paired Chrysler's E86 440-cubic-inch four-barrel V8 with the heavy-duty TorqueFlite automatic. The engine was rated at 280 net horsepower, and the U in the VIN's fifth position identifies this factory engine path.
Ordering the 440 also brought subtle GTX badges. That did not revive the GTX as a separate model or create a separately named package in Plymouth's literature; it remained a Road Runner with the top engine and the accompanying badges.
The reviewed secondary production reference reports 749 U.S.-spec 440 Road Runners within 19,056 total 1973 Road Runners. Every 440 car used the automatic. Those figures remain source attributed until a direct Chrysler production record is reviewed.
Twenty-four named exterior colors and seven interior shades are documented. Bucket seats, a console, Rallye instrumentation, power front discs, air conditioning, an electric sunroof, and several appearance treatments were available, but an individual car's fender tag and broadcast sheet must establish its original equipment.
For authentication, begin with the RM Road Runner model characters and U engine character, then reconcile the complete VIN with the fender tag, broadcast sheet, body stampings, engine and transmission identifiers, dates, paint, trim, and options. A 440 swap, Road Runner graphics, or GTX badges alone cannot establish a factory 440 car.