I think he got tired of taking the latest Ford Shelby, giving it more power, and then the very next model year Ford trumping it with the production car. I think he felt safe at 1000HP not being 1 upped by Ford.
The motor has to be some serious $$$$, they had to cut corners somewhere lolThat car is a cool build and all, but they really lack in the exterior. Those Shelby 1000 stickers are just plain ugly.