Caterham Cars Demonstrates New Chassis Design to Cut Weight 10 Percent
Butted tubing shaves precious pounds off the Seven.
The Caterham Seven is a pretty light, back-to-basics car as it stands, but the British manufacturer would love to shave even more mass from its elemental sports car. In pursuit of that goal, Caterham has revealed a prototype Seven chassis that's as much as 10 percent lighter than the current design.
Working on partnership with bicycle-tube manufacturer Reynolds Technology and consulting firm Simpact Engineering, Caterham replaced most parts of the Seven's chassis with butted tubes. Inspired by the construction of bicycle frames, butted tubes are thinner in the center and larger at either end, which Caterham says improves stiffness while reducing weight.
Even though the prototype Caterham Seven chassis seen here is 10 percent lighter than one made without butted tubes, Caterham says structural and torsional rigidity have not been affected. In fact, the design is said to save money because engineers can get adequate strength out of lower-alloy steels rather than exotic ultra-high-strength steels or pricey carbon fiber.
Caterham says that using butted tubes in a Seven sports car would add about $1,400-$2,800 to its cost. But the manufacturer also believes many buyers would be interested in the weight-saving option, and plans to put butted-tube chassis designs into production as soon as possible.