That's a very good point Chrisl,
I was thinking about this yesterday and pretended that there weren't any rules. What would it look like out there? Extreme use of ground effects and aero quickly came to mind. Remember it did result in an up surge in fatal accidents prior to being ruled off imits in F1. During Can-Am's hayday the science of Ground Effects had only begun to be understood.
I'd have to agree with Chrisl that the designs created by the engineers might (no doubt would) conflict with the survival of the drivers and that's not good for anyone or racing as a sport and profession.
To Imaginary '40's point about big , small and light or heavy, I just received a DVD from a friend featuring the Can-Am team of Oscar Koveleski's efforts. In his interesting narrative he mentioned how due to the size of those huge engines the gyro-effect created by the moving parts inside the power plants physically effected the handling as the driver cometed with the engine for control of the cars. The "gyro" (engine parts) wanted to hold its course like gyros are suppose to do, while the driver wanted to turn. Consequently, there was as much competition within the car as there was on the track. Today's engineering advancements in engine design and materials used allows for the same, and far greater, power achieved in power packages 1/3 the size.
If there were a way to eliminate the the rules from racing without sudstantially increasing the dangers to drivers it would be a perfect world. I can't see that as realistic when the whole purpose of racing is speed over distance and as soon as you increase the speed with better, more powerful engines, suspensions and the harnessing of the wind above and beneath the car, when something happens the increased speed attained wrecks mens' bodies 'cause the ground and other structures stop them too quickly.
So.... after my afternoon of imagining what it would be like without rules I came to the conclusion that due to the capabilities already realized ... we probably will never see anything like the unlimited Can-Am rule book again. That, in itself, makes that part of racing history extrodinary and something to charish!!!
Cheers,
Dick Bear