Same block, right (not an FE for one and a Windsor for the other)?
The bigger motor, all other things being equal, yields more torque, ergo more fun on the street; or conversely, yields equal HP/torque figures with a much less "tweaky" build.
What would be, to me, more important would be the quality of the components.....if I had to choose between a 402 with forged internals and a 427 with cast internals, I'd go for the 402. Can't imagine much else that would make me choose the 402, though.
Cheers from Dugly
