[WarrenG]

Can't speak to either of the 427 cars, but I know that my ERA FIA is quite happy at 115 mph. It actually seems to get "tighter" to the road at that speed. Not sure it would be comfortable noise wise for too long though without earplugs. I'd think you'd be going deaf quickly just from the road noise.

Supposedly, these cars, aerodynamically, are like a brick when they get up to around 150 mph. Not sure sustained 140-160 is a realistic expectation. But then that's what everybody said about the F-4 Phantom originally also and they just put bigger engines in it!

I would expect the ERA 427 to be similar not sure about the SPF but one thing the SPF has over the ERA is that it would be a much faster lead time for a new one.