Eric Broadley's T70 sports prototype was upgraded from the same successful formula as the Mk I by having an American-sourced V8 engine in a small prototype chassis. Most of the successful cars were run with the small-block Chevrolet engines, but one victory was achieved with the Ford 333 and Penske tried the 427 Chevrolet with no success whatsoever. The MkII specification introduced much more aluminum in the chassis which reduced the overall weight by 32 kg (70 lbs). More weight was saved by using color-impregnated fiberglass. This resulted in a 289 Ford-powered T70 weighing just 726 kgs (1500 lbs) while the Chevrolet 327 was at 726 kgs (1600 lbs). Other small changes that came with the Mk II were wider wheels, consolidated radiators with one large cooling unit in the nose and revised suspension points. In total 33 MkII Spyders were built and this series is the most successful of all the T70 variants. Denny Hulme won 11 races in Europe driving SL71/31 for Sidney Taylor winning the first of five races outright including the Tourist Trophy at Oulton Park. The first Mk II was delivered to Team Surtees and John won first time out at the Guards Trophy Meeting at Brands Hatch. Drivers such as Graham Hill and David Hobbs drove for the Surtees team with great success. Brian Redman also scored two victories for Red Rose Racing in SL71/27. In 1966 16 cars were delivered to the USA and won the USSRC championship in both 1966 and 1967. Being the US agent, the Mecom Racing Team was under great pressure to perform. They sold the cars to private teams which used drivers such as George Follmer, Dan Gurney, Mark Donohue, Roger Penske and Buck Fulp. T70s won the first two rounds of the CanAm championship in 1966 which was eventually won by John Surtees.