Zero downforce F1 vs roadcars. When did roadcars getquicker?

[glazbagun]

If they did at all?

I was just watching this vid of Clark & co in the 60's:

http://www.youtube.com/watch?v=r_PxCW8uS9g

...and it made me wonder- when did roadcars get faster than the best of the zero downforce F1 cars? If you were to bring a modern cooking Caterham or a despoilered Subaru to the above race with a bit of hillclimb experience, could you leave them for dead or would even a top drawer driver struggle?

Edited by glazbagun on Tuesday 22 April 22:26

[glazbagun]

Just found this.

http://www.f1fanatic.co.uk/2014/02/17/f1-car-power...

According to this the 67 McLaren was pushing near 700HP/ton sans driver, but it quickly took a huge leap. I guess that's going to be pretty much uncatchable if the brakes and tyres are up to the job.