Notes on the Cars at Brands Hatch
The Daily Mail Race of Champions meeting at Brands Hatch saw the first appearance of new cars from McLaren Racing, the Owen Organisation B.R.M. team, the Cooper Car Company, and Matra-International, as well as a number of well-proven cars. There were two McLaren cars, M7A-2 for Hulme and M7A-1 for McLaren himself, both powered by Cosworth V8 engines and driving through Hewland gearboxes. The car is designed on similar principles to that of the Lotus 49, in that the V8 engine is fixed rigidly to the bulkhead behind the cockpit and forms the rear part of the chassis, a welded framework attached to the rear of the engine carrying the rear suspension members. Front suspension is by widebased A-brackets, with interposed coil spring/damper units, and conventional Grand Prix practice with lower A-bracket, single trans-verse top strut and two radius rods on each side looks after the rear end. Radiator-air exits from two large openings on the top of the nose cowling and the cockpit has a full wrap-round screen of green tinted perspex. Fast in front of the screen in a flap, fastened by an aircraft-type flush fitting catch, which conceals the fuel filler. At the moment there is no bodywork aft of the cockpit, but provision is made for more bodywork at a later date. The glassfibre nose cowling has a high gloss orange finish and the cockpit and driving seat are beautifully upholstered in black quilted material. At the back of the car, on the left of the gearbox is a large black cylindrical container holding the oil for the dry-sump Cosworth V8 engine, with an oil radiator mounted above the gearbox. The disc brakes have special Lockheed calipers with four pistons, instead of the usual two, and these operate on large single Ferodo pads on each side of the disc. Due to a last-minute shortage of parts there was only one complete set of these new brakes for Hulme, so McLaren settled for 4-piston calipers on the back and twin-piston calipers on the front. The whole finish of the two cars was extremely praise worthy, while the detail work, especially of small machined components, would have done credit to Daimler-Benz or Vanwall racing cars, and showed a delightful “pride of workmanship” on the part of the McLaren workers.
The new B.R.M. cars were both powered by 3-litre 4 o.h.c. V12-cylinder engines, driving through Hewland 5-speed gearboxes, until such time as the new Bourne gearboxes are ready. When this 12-cylinder car project was started it was given to Len Terry and his design office and they built three cars, known as P126 models, the first two having 2½-litre engines installed for the Tasman races. The third car P126-03 had a full 3-litre engine in it and was driven by Spence at Brands Hatch, having also done all the pre-race testing. The fourth car was built at Bourne to the same Len Terry design and is designated the P133 model, and this was driven by Rodriguez. Unlike the McLaren, the Lotus 49 and the H.16 B.R.M., in which the monocoque chassis structure finishes behind the cockpit the V.12 B.R.M. monocoque chassis runs the full length of the car, forming a cradle from the cockpit rearwards, in which the engine sits. Front suspension of the P126 and P133 cars follows the pattern of the H.16 cars, with inboard coil spring/damper units operated by a rocker-type top wishbone arm, with a lower wide-base A-bracket. At the rear the suspension has an unusual layout, in that instead of a lower A-bracket there is a rectangular shaped tubular bracket locating the bottom of the hub carrier. A single top arm and double radius rods each side follow standard practice. The pivots for the lower bracket are on a tubular sub-frame extending from the rear bulkhead of the monocoque, with the Hewland gearbox lying in the middle of it.
The Ken Tyrrell team of Matra-International, backed by E.L.F. petrol, had the first of their new cars, MS10-01, which was built in the middle of February. In this car the Cosworth V8 engine is not used as a chassis member and rear suspension carrier, for there is a tubular sub-frame bolted to the end of the cockpit monocoque and running rearwards to a steel bulkhead, an alloy plate between the engine and the Hewland gearbox carrying the power unit on this framework. To give clearance for the large final drive universal joints, which are combined rubber “doughnut” and mechanical joints, the starter motor on the left of the gearbox is mounted at an angle and drives forward through a universal-jointed shaft. Oil is carried in a tank in the nose but there is an oil radiator mounted above the gearbox, just above a plate carrying the Lucas electronic ignition equipment. The driver’s seat is made of glassfibre, as are the nose cowling and the oil breather “catch tank,” while behind the driver’s head and under the very solid double-tube crash bar is a “pull-knob” for operating the battery master-switch by cable, the switch being mounted on the left side of the gearbox, near the battery.
The new Cooper, designated the T86B, follows the general principles of the very flat 1967 Cooper-Maserati, with a full-length monocoque chassis structure, with “rocker-arm” front suspension and conventional rear end and has the same brake layout with the discs inboard of the hub carriers, but not completely inboard as on the Ferrari for example. The 1967 style welded sheet-magnesium wheels are used, and the rather “sports specification” V12 B.R.M. drives through a Hewland gearbox. The latest GP version of the engine, as distinct from the GT version, was not ready in time to build into the car. The differences in these engines is only detail, on such things as compression ratio, pistons, valve gear and connecting rods, the basic 4 o.h.c V12 layout with two-valves per cylinder, is unchanged.
The three Ferrari cars were their 1967 models, all with 4-valve-per-cylinder V12 engines and the latest 5-speed gearbox with the selector mechanism on the top and a system of rocking levers transferring the movement from the right-hand gearbox lever. The engines had side inlet ports and exhaust ports in the centre of the vee, and Amon drove 0007, Ickx 0003 and de Adamich 0005.
The single Team Lotus entry driven by Hill was 49/5, the last of the 1967 cars to be built, 49/4 having been sold to Rob Walker and Jack Durlacher. As a temporary experiment in weight distribution the oil tank had been moved to the rear, as well as the battery, but the experiment did not appear to be a success, for the handling was visibly bad.
The mechanical interest at this meeting was of a very good standard, especially bearing in mind how early in the season it took place, the next Formula One outing being at Silverstone on April 27th at the Daily Express meeting run by the B.R.D.C., while the first Championship event is not until May 12th, when the Spanish Grand Prix takes place on the Jarama Circuit near Madrid. The McLaren cars would appear to be finalised in general conception, future modifications and improvements coming under the heading of racing development. The V12 B.R.M. cars will no doubt eventually have Bourne built gearboxes to replace the Hewland gearboxes, and the cars are said to be in the nature of a temporary expedient while the H.16 cars are undergoing further improvement, but if the H.16 cars do not make great strides forward then B.R.M. may find themselves embarrassed by the “wrong” cars being the most successful. The Matra MS10 is something in the nature of an interim car, for doubtless the French will want the all-French V12-engined MS11 car to win races ultimately, but as it is at present the MS10 will provide the Tyrrell/Stewart combine with good racing material. The Lotus 49/5 that Hill drove was very much the last of the 1967 effort, and would have appeared earlier had Lotus kept up to schedule with their racing programme. New Lotus cars for 1968 are under way and a 4-w-d investigation is well advanced. The Cooper-B.R.M. V12 is an extension of the 1967 programme, but doubtless there is some advanced design thinking going on at Byfleet, which should materialise during the 1968 season. At the moment there have been no signs of the 1968 Ferrari design thinking, but by Maranello’s normal standards the existing cars and engines are obsolete, and by Monza-time in September something entirely new should have materialised.
The fact that Brabham and Eagle missed the Race of Champions means that they are both one race behind their rivals, but Repco are well advanced with new engine designs and it never takes Brabham and Tauranac long to make up a new chassis. Eagle are concentrating on becoming self-supporting at the moment, having severed all connection with Harry Weslake Engineering. They are already building the Weslake-designed V12 engine themselves in a new factory, and intend to carry on engine development work on their own. In California the parent branch of A.A.R. are concentrating on new cars for Indianapolis, for not only has Dan Gurney got the ambition to win the 500-mile race with one of his own cars, but he also has the ability to do.—D. S. J.