Really?
Because from my point of view the only real difference between a "street" and "race" part was what you were willing to put up with in a street car and what you were willing to spend.
The real change has come in the affordability of parts. Chinese parts. Cheap alloy heads, cheap rods and cranks, EFI controller, turbos, etc..
If you could have bought all that stuff cheap decades ago, we'd all have been using it.