For five consecutive Cam-Am seasons, works
McLarens steamrollered all opposition by winning 37 out of 43 races to take
the title every year.
Story by Mark Hughes, pictorial evolution by Doug Nye.
The M8F marked the zenith of McLaren’s extraordinary run of success in the big-buck Can-Am Championship between 1967 and 1971. Rarely has a single marque dominated a top-level race series for so long and with such overwhelming force. Apart from taking all five Can-Am titles in this period, McLaren cars won 37 of the 43 races, including an incredible sequence of 19 successive victories. No wonder this motor racing legend will forever be nicknamed "The Bruce & Denny Show"…
In retrospect, it seems curious how, with such substantial prize money on offer, McLaren could have been left for so long with a near monopoly of these handsome commercial rewards. But then success breeds further success. As well as delivering sporting achievement, the Can-Am was significant as a nice little earner for the Colnbrook-based team, at a time when Bruce’s embryonic operation was struggling to make its mark in Grand Prix racing.
"Can-Am was the making of McLaren,", recalls Teddy Mayer, now working for Penske. "It financed the growth of the company, which was then able to go into F1. It paid very well if you finished first and second most of the time, and through 1969, our best season, we were usually picking up prize money in the $50,000 - $75,000 range at each race. And then we were always able to sell the works cars for good money at the end of a season, and more came in from the customer cars built by Trojan. But it was a lot of fun too…".
M6A Founds a Dynasty
The bedrock of McLaren’s super-successful pyramid of Can-Am cars was laid with the M6A, a new design conceived after the team’s somewhat disappointing first Can-Am season with the M1B in 1966. There had been flashes of form that year when the M1Bs, driven by Bruce and Chris Amon, led a couple of races, but Lola and Chaparral had the class cars. John Surtees (Lola) took the title, Bruce and Chris trailing in the championship standings with third and sixth places respectively, neither taking a win.
Stung by Lola’s domination, the team entered 1967 determined to do much better in the lucrative Can-Am. Robin Herd, later to become one of March’s founders, began sketching out the all-new M6A, the first car from any manufacturer to be engineered specifically for the Can-Am. Although Chaparral’s Jim Hall described it as "a common car, done uncommonly well", the M6A was a carefully judged blend of state-of-the-art structural techniques and conventional running gear. It was designed to be light, simple and pleasant to drive.
Dispensing with the traditional tubular spaceframe chassis, the M6A was the first McLaren sports car to use a monocoque, this short but wide structure being made from panels of magnesium and aluminium held together by aircraft rivets and epoxy resin. Three fuel bags within the monocoque – one in each of the side boxes and a third in the transverse cavity beneath the driver’s knees – ingeniously delivered their 54 gallon capacity to the engine without an electric pump. One-way valves in the system allowed the fuel to wash around with the forces of acceleration, braking and cornering, so that the right-hand tank, from which the engine was supplied via a fuel collector pot and mechanical pump, was kept full.
In essence, this structure became the basic building block for McLaren’s five seasons of Can-Am supremacy, although designers Gordon Coppuck and Jo Marquart would produce year-by-year improvements. In Teddy Mayer’s words, "Robin was responsible for this key breakthrough in showing us how to build a nice, light, rigid Can-Am chassis". Weighing just 1354lb (615kg), the M6A would be the lightest car in the 1967 series, and nimble too.
Since the M1B had proved itself to be a good handling car, nothing radical was attempted with the M6A's suspension. Top and bottom lateral links located by trailing radius rods were used at the front, while the rear featured a lateral top link, lower wishbone and twin radius rods. Unlike Lola, McLaren mounted the brakes conventionally within cast-magnesium 15in wheels, which were of a massive 13.5in width at the rear to carry the latest generation Goodyear tyres.
Through the summer of 1967, leading up to the late-season September 3 start of the Can-Am series at Elkhart Lake, the M6A was tested more extensively than any previous McLaren. Sticking to his belief that a chassis should be set up before aerodynamic factors were considered, Bruce started testing the car in naked form before the first glass fibre panels from Specialised Mouldings were added. Showing how hard he went sans bodywork, Bruce’s best first-day time at Goodwood was less than 3sec adrift of Denny’s ultimate pre-season standard of 1m 13.4s.