So is a I6 1964 Mustang not a pony car? What about something like our 67 Barracuda witha 273 commando?
I think in the pony car realm, engine size doesn't matter. you could get screaming cars with small engines, take the old v6 corvettes, for the time they were quick, and they were small in the engine department.
That's a cool arcticle though. but raised a fe questionss for me.