The new 5.0 is a stellar engine. If you can get the 5.0 with track key technology you can have you cake and eat it too as far as ease of maintenence, track readiness and lopy sound. It will never match the torque or hp from even a good 351W which can be built up to crazy power levels.
In a Cobra, however, (and this is for me and my personal tastes and MHO only) the idea is to recreate what the beast was as close as possible. A new 5.0 takes you as far away from that as would installing the warp drive from the Millenum Falcon (almost
). I think the new 5.0 with track key technology would make for steller track car all things considered though but so would a good 351W or well built BB. I would hesitate to use an original 427SO for track work though. The expense of these blocks and relative rarity would make me hesitate.
But some guys like to build the car to suit their own tastes and likes. Thats what make the hobby interesting.