The original Ford GT40 MkI took the world by storm. But the competition was not standing still. Ford knew Ferrari was working on something - ultimately the 330 P3/4. So Ford leadership was not convinced that the British built GT40 Mk1 was going to win LeMans, with its steel monocoque and small block V8. They called Carroll Shelby, and asked him to further develop the existing car. He firsdt fitted a larger version of the small block engine, installed new cast alloy wheels and better brakes. The car was instantly successful. The Shelby-enhanced GT40 won the Daytona 2000 km and its class at the Sebring 12 Hours. Shelby decided to go bigger for Le Mans. He equipped two cars with the Ford Galaxy derived big block V8. The resulting GT40 Mark IIs were quick, but fragile and Le Mans was a disaster for Ford once again.
Shelby continued to develop the big block engined GT40 Mk II, but Ford had even bigger plans. Eric Broadley, the genius behind Lola, had said from the start of the GT40 project that using steel for the car's monocoque wasn't a good idea. The team knew the only viable solution was to build a heavily revised version of the chassis.