Rare 1967 Mr. Norm's 383 4 speed dart

The reason the '67 A bodies were widened was so they could put a B engine in. They saw that in the upcoming 1967 model year GM was going to have a 396 Camaro and 400 Firebird, and FoMoCo would have the 390 Mustang and Cougar, so they didn't want to get left behind in the hp wars.