but then in the 70s F1 with wild chassis and aero and V8, V12 and turbo V6 was still wild.
Two-stroke or Diesel would have been legal, too, but of course not tried out.

Also, Group 5 with Moby or Zak Capri and such was wildly experimental and rule bending.

And Group B in rallying of the 80s.

All these were dangerous as heck, and kinda disrespecting the health of even their most precious and valuable star drivers.