Paul, if you put the usual go-fast bits on a 302 you'll find it's plenty on the track. That's more hp/weight than most exotics including recent ferraris or porsches, for example. A well set up GT40 will outdrag a ferrari 360 or a new 911, and, hang with them in the twisties.
I figured as much. The cars a quite light. I feel like a kid on Christmas waiting to get a GT40. I felt this way when I bought my Lotus esprit. The "P" cars couldn't keep up with that car in the twistys. I've not yet driven a GT40 replica so I don't know how they handle in the corners, ( imho )
Thats where the race is won.
Thanks for the phone call. You're a true enthusiast
About the engines, a good 302 will be easier to drive on the street than a big cube. Kind of like the Miata, lot's of people gripe it's underpowered, in reality it's a blast to drive because you can keep your foot in it.
A big power GT40 (500hp+) has so much oooomf you'll barely get off the idle circuits! Although they say there's no substitute for cubic inches...