I watched Peter Windsor's interview with Brian Redman last week. Brian stated that back in the day, sportscars were lapping the old Spa 7 or 8 seconds faster than the Grand Prix cars, with the Porsche 917s hitting 210mph on the straights compared to Grand Prix's 180mph or so. I checked this out and sure enough he was right. 1970 Belgian GP, the fastest lap was a 3'27. In the Spa 1000km a month earlier, Rodriguez pulled off a 3'16. The weather was comparable for most events. That's a huge difference in lap time.
Is this any basis to say that Grand Prix cars were behind sports cars at the time?
The reason I ask is that it looks like "the pinnacle of motorsport" is falling behind sports cars again. Sports car technology is far more pioneering, running hybrid systems, energy recovery systems, alternative fuels, very experimental cars such as the Deltawing and while F1 is giving some of these a go, the systems are nowhere near as reliable and it has been embarrassing to watch manufacturers like Honda struggle to make cars that'll last more than a handful of laps at full beans. Not only that, but modern Grand Prix drivers "race" at several seconds off the pace because they're forever "managing" their cars whereas the LMP1 prototypes are seemingly driven flat out much of the way. And I doubt I need to go into the calibre of Grand Prix drivers vs. sports car drivers. Let's just say if you're 18 and you have a lot of money you can do whatever you want.