On the subject of Pony vs Musclecar...
I like to think of it as small block and big block, in that case. Pony Cars as a class were "created" to compete in the Trans-Am series. They are, by nature, road racers. They're small, near-compact 2 door coupes with a functional back seat, a V8 and RWD, designed for a BALANCE of handling and straightline performance.
As a result, your 64-73 Mustang with a smallblock is a pony car, as is a 69+ Camaro and Firebird, as is a 64+ 'Cuda or Valiant, as well as the 67-69 Cougar, and I suppose a Javelin as well. And the Challenger T/A and AAR 'Cuda.
But when you put bigblock in any of these cars, the whole package really changes to a drag car. Ever driven a big block Camaro? I've never driven a COPO or a ZL1, but I have driven an SS396, and it handled like GARBAGE compared to a Z/28. That to me is the distinction. I'd call those musclecars.
Just my
