Is there a faster way around a given track than current F1?

[humpbackmaniac]

Just musing over speed, and I was wondering if there is currently a faster way around a given track, say Silverstone, than a modern F1 car? Short of using a 2009 or older car with more aero, I appreciate lap times were slightly faster then, but if an Open Class existed where anything was possible what would teams build and would we watch them race?

[humpbackmaniac]

Thanks for all the replies. So an existing F1 and a boost up to the heady days of 1500hp seems to be the overall view.