[Ralph]

The 2021 Cup cars will be a lot more modern, closer to what they sell today. IRS, and different ways to make down force....so air can go under cars again....giving some cooling to cars behind.

Then in 2022....rumor is no more push rod engines. Current push rod engines have evolved so far....they hardly ever blow up anymore...with HP levels between maybe 450 and 900....depending on intake size. Rumor is overhead cam V6's and maybe some hybrid tech like the coming Indy engines. Problem is making that tech last 500-600 miles at max RPM on some of these tracks. Ford, GM, Toyota, and Honda all make V6 3.5 L 4 valve engines. Rumor is Honda may join. Even Chrysler could build a race engine off their 3.6 V6.

The current push rod engines can run 8000-9000 (or slightly more) RPM's all afternoon long and survive. You can watch them bump off the rev limiter around 9600 on TV. An amazing engineering feat for a big engine....even for old tech.

NASCAR has some amazing new tech based on 1960's tech. Watts link solid rears, with camber and toe adjustment on rear...how do you do that on a solid axle car? They do it.