I discover I have only been tickling the throttle. My foot sinks ten inches and the grenade goes off

Couldn’t happen, could it? Well, not today, but it did and it’s sort of a military theme. If you asked a NASA scientist in the 1960s to get a rocket to the moon, he wouldn’t ask if there were any restrictions on size or fuel consumption. Or budget for that matter. All that mattered would be getting there. CanAm was a bit like that, the race series created in the mid-1960s to embrace the American dream that anything was possible and, preferably, the bigger the better. The only stipulation was that the car had to have two seats and enclosed wheels.
 
So you had engines of seven, eight, even nine litres; tyres 17 inches wide, exotic materials, multiple engines, ground effect and wings the size of a Beechcraft mainplane, all of which represented the biggest and best of what they knew in 1970.

It’s unfeasible now but the chaos from complete lack of regulation that seems so inevitable was actually restrained by the technology of the time. Carbonfibre hadn’t been invented, car aerodynamics were rudimentary, Colin Chapman had yet to plagiarise ground effect (although CanAm’s equivalent, Jim Hall, produced a car with a snowmobile engine driving two fans that sucked the air from under the car…) and tyres had only just stopped wearing treads. Electronics weren’t available to keep a turbocharger from melting an engine; while Porsche found a way to do it in 1973 with the 1100bhp twin-turbo 917/30, it nearly killed the formula because nobody else could. Or perhaps by then the American auto industry’s love affair with CanAm was over and the money was going elsewhere.
 
The 917/30 remains the most powerful circuit race car ever made but, until then, a big-block Chevrolet that started life at 7.0 litres was the largest and most powerful available engine that would fit into a car, and most subsequent regulation would seek to restrict exactly what it liberated. A CanAm car might look relatively unsophisticated now, but it ushered in ground effect, skirts, wings (movable and fixed), four-wheel drive and aerospace materials into motor sport, and, as a result, the cars were often faster than the Formula 1s that went on to embrace all of those. CanAm was certainly out there at the edges of the envelope.

And CanAm produced the most powerful race car an amateur could buy. It was so in 1970 – and it still is. The McLaren CanAm car in these pictures – M8E no 80-06, now owned by enthusiast and racer Stephen Minoprio – was bought from the factory in 1971 by one Fred Parkhill, who ran his eponymous liquor store at 5111 South Lewis Boulevard in Tulsa. It came with a Hewland five-speed LG500 gearbox but without an engine, which makes sense since the car was made in England and the people who knew about Chevrolets were in America.

The horsepower race was already on. Parkhill built his own engines in the great American hot-rodding tradition and takes up the story. ‘I started out with a 427 and the big guys went to 465, so I got one; then they went to 494. I got one. Of course, after that, they went to 512. I gave up then…’

That an amateur could mix it with the likes of Gurney, Stewart, Donohue, Foyt, Andretti, Hulme and the rest is something for which I’d have given anything in my formative years but Fred raced the car in official CanAm just the once, at the 3.1-mile Donnybrooke Speedway in Minnesota, in 1971. He qualified 15th and finished 15th, but he was there… with the best in the world. Fred went from there to less-challenging events, like the grand prix in Ponca City, Oklahoma, where in 1975 he set a track record that still stands! Speed has always cost money: 512ci equates to 8.4 litres and in 1978 Fred sold the McLaren for something less expensive. He had raced the car fewer than a dozen times. CanAm engines grew bigger still but Fred now owns a Lola T332 Formula 5000 car, which he says he is ‘too old to race’ but takes out ‘once a year to have some fun’. Respect.
 
The CanAm series began in 1966, with John Surtees winning the inaugural championship in a Lola T70. But by 1968, Kiwis Denny Hulme and Bruce McLaren had begun the ‘Bruce and Denny Show’ with the latter’s dramatic-looking racers and put their grip on the championship. The M8E was intended as a customer version of the M8D factory car that had trumped the 1970 CanAm in the hands of Hulme, American Dan Gurney and Englishman Peter Gethin, but was shuffled aside by 1971’s ‘F’ model, a razor-edged orange monster with dramatic aerodynamic fences.

Hulme was less than enthusiastic about the F, saying that it had too much downforce in the wrong places. The E, he felt, was smaller, more slippery – and faster. The factory stuck to the F-plan but took note of Hulme’s comments and made the customer car slightly shorter and narrower. Hulme tested the M8E in 1971 and liked it but only ten were ever made. Eight are known still.

Let nobody suggest an M8E is anything but large, though. When it greets me at the HSCC’s Silverstone test day, it looks simply enormous, an impression heightened by the huge rear wing, the snaggled row of inlet trumpets, and the vertical Kinsler/Lucas injection pump that together feed the Chevy V8. All of which soon seem minimal in comparison with the noise it generates.

On hand to assist is New Zealander Ian Jones of Suffolk-based Racing Fabrications, who rebuilt the car and replaced the 5.0-litre small-block V8 mandated by 1980s UK regulations (strange how history repeats itself) with a 532ci (8.7-litre) all-aluminium pushrod Chevrolet built by Kirt and Bud Bennett in Wixom, Detroit. It pushes out 860bhp and 750lb ft of torque and, to handle it, the original Hewland transaxle (a weak point in-period) has been replaced with an uprated version produced by Charlie Agg – son of Peter, original boss of Trojan, which built the McLaren customer cars.

Once the car is denuded and the bodywork removed (a couple of minutes’ work for Jones’ team), it’s very simple under the skin. The suspension is almost identical in design and layout (double wishbones at the front, transverse links and radius rods at the rear) to a Formula Ford’s of the period – just larger and with a big riveted aluminium monocoque tub in-between. Nice too, according to Jones. He says the detailing and finish of the parts were ahead of most of the opposition at the time, pointing out the neat little strengtheners on the wishbones and chassis, the latter zinc chromate treated for anti-corrosion. All, he says, made in a ‘very McLaren way, very aviation’.

Yet it’s amazingly light – two men can lift the monocoque tub – and, even with the huge engine and gearbox installed, the whole lot weighs in at just 850kg, for 1024bhp per tonne. Mechanic Sam Richardson is busy squirting neat petrol down the trumpets while Jones spins up the engine on the starter, then flicks on the ignition – if the engine fires before it’s properly churning, the advance kicks it backwards and smashes the starter. Much can break on one of these and, as the knowledge of what and where filters through, I get a sense of a gladiatorial contest. A battle of man against man in racing, but also man against machine.
 
The engine fires with a shattering bellow that summons watchers from all corners of the paddock. A modern Formula 1 car has a shrill intensity that hurts – this has all that underpinned by the biggest bass box imaginable. Its multi-layered energy gets you like every instrument in a huge amplified orchestra playing together at maximum volume. It spins up quickly, too. Accelerator travel is hugely long for good reason, yet the merest touch sends the needle round the dial like the next frame in a movie.

There is nothing else like the noise and throttle response of a top-spec big-block and the reason is the lightness of the internals relative to the displacement. It takes two men to lower the crank accurately into the block but, as a percentage relative to the massive 8.7 litres, the weight of reciprocating parts is much less than it is in, say, a 3.0-litre Cosworth DFV, or a modern 2.0-litre four such as Ford’s Duratec.
 
The flywheel is tiny, and has to be to fit inside the Hewland’s bellhousing and clear the ground, so the driver has to be very careful. Jones leans in and offers words of caution. ‘It’s easy to keep to 7000 on the way up,’ he says, ‘but they always get over-revved on the downshift when the driver gives the throttle a blip.’

The rest is reasonably comfortable and I lie back in the tub with plenty of room for legs and feet, looking at a dash with an absolute minimum of dials and switches. The gearlever sits lonely on the expanse of tub, and I pull it across and back for first, then head towards the Grand Prix circuit. Already the way the engine spins and the weight of the clutch need managing, one slow and heavy, the other hair-trigger light, but soon I remember to hold one at a constant and feed the other against it.

There’s a curious sense of ease and calm because the controls are just like those of any other sports car of the period, which is to say light and simple – but controlling the pent-up energy that lies behind feels like pulling the pin of a grenade.

Onto the circuit, steering eerily light and easy, carefully guide the lever across and forward for second, feel the gentle clatter of the dogs, see that the revs have fallen away to tickover almost as fast as they spin up. Let the clutch up with a jerk and gently squeeze the gas. It’s massive but, so far, not other-worldly. Pull back for third. Another squeeze, another massive surge, ease it through Maggots, Becketts and Chapel, looking for the calm of the Hangar Straight. It’s cold so I lean on the tyres as much as possible without trying to accelerate the car. Get at least a little warmth into them.