[Jack21]

Probably not the answer you wanted however...

Being an old Pontiac guy myself, I'd drop the 455 Poncho into a vintage GTO, '79 - earlier Trans Am or sleeper '70's vintage LeMans or Oldsmobile Cutlass size station wagon.. Too big, too hot, too heavy, and all the torque on the wrong end of the curve for a Cobra; not to mention all the engineering and custom parts to get all to fit. Although trans wise, the Richmond 4, 5, and 6 speeds would bolt right up.

That being said, a 455 Buick would make an interesting Cobra powerplant. Big bore, short stroke, high revving, and lightweight compact block...in anything but an FFR.

Although I've got a CR, half the guys in our club own FFR's, and shoehorning anything bigger than a 302 into them gets tricky. Stroker 302's and blowers seem to be the way to make FFR's go fast (very fast).

The T5Z makes a nice choice for small block power, and the G-Force gearset swap would be my choice for anything over 400 HP.

Lastly, anything but Ford power in a Cobra kills your resale value.