I know it was a road car. Similar in theory to the RS500, so many of these engines were built so they classified as legal in NASCAR in a Taledega, the head guy at Ford thought the Mustang was a more suitable shape to put the engine into as it has sporty heritage. Bit like an RS500 engine into a Capri.

The engine was so wide I beleive they had to modify the suspension towers to get the engine in!

The 427 SOHC engine is highly prized by collectors and racers alike.