Them three replicas are bloody awesome! The specs seem to be off, but they are pretty damn good. This may, however, be down to the fact that they are three of my favourite cars, especially the F-Type!
I remember making a pretty close-to-perfect Mulsanne engine (only torque came in too late and there wasn't enough of it due to the game's turbo calculations being off), and I know for certain that it doesn't hit 7000 rpm . I'll have to see if I can find it.