I've raced against these cars with the local vintage club. A track-prepped vette is a much faster car than most Porsches you'll see at the track.
I'm no expert on the 454 vs small block engines, but I will say the one race I was in with a "7 liter" vette, that thing was by far the fastest car in the race.
IMO, the stingrays are making a comeback as far as being 70s vintage cool now. If it were me, I'd get one of those.
