This is the Ford GT40. The GT40 won Le Mans in '66-68 or '69.
The engine made it into just enough production cars.
Chrysler pushed Nascar to ban it. I'm not sure on what grounds though. About the only one I heard was that it would push speeds to high. I've looked around to see if anyone has put a SOHC in a GT40. I've read of maybe a couple of people talking about it, but haven't seen anything definitive.
Its a BIG engine, in a not very big engine compartment.
It would be a beast of a car.