It was BRM's first attempt at the monocoque design introduced by Lotus a year earlier.

Fundamental design issues would mean the car only competed 2 Grands Prix before being garaged in favor of the older, more reliable spaceframe P57.

After the success of Jim Clark and his Lotus 25 in 1962, BRM began work on their own monocoque car.

BRM's designers, confident in their chassis' rigidity, omitted a rear bulkhead between the driver and engine.

Although the result seemed promising, it immediately became apparent the car suffered from severe chassis flex without a bulkhead.