[JayBar]

Hey, NHRA is some what the same. Take Funny Cars. The announcer says here comes the Chevy or Pontiac, when in the only thing Chevy or Pontiac is the name on the front of the car. There is not one GM part on these cars.
AS for NASCAR I would bet there are no Ford or Chev or Mopar parts either.

They must use World or Dart or some other beefed up Blocks, custom heads and all other accessories.
I stopped watching NASCAR when they stopped using Stock cars (read, cars manufactured by Big Three).

Now I must confess I have a Backdraft Cobra. I have a Dart block, AFR heads,
Edelbrock manifold, etc. But I do have Ford Valve covers, so I guess I can call it a Ford.