Of particular interest were the two 3-litre Porsches, making their first rate appearance, though they had appeared publicly at the Le Mans test-weekend. The body/chassis units were similar to the 2.2-litre long-tailed 907 cars, with a tubular space frame with the glassfibre body bonded to it. Designated the 908, the new cars had entirely new engines and gearboxes, the only similarity to the 2.2-litre cars being the horizontally-opposed layout of the eight cylinders. Whereas the 2.2-litre 8-cylinder engine was developed from the old 1½-litre Grand Prix engine, with bevel gear and shaft drive to the camshafts, and a horizontal cooling fan on the top of the engine, the 3-litre 8-cylinders are developed from the 6-cylinder series, with chain and gear drive to the four camshafts from the front of the crankshaft and a vertical cooling fan driven from this drive train. The gearboxes were a new design, being of six speeds and having the clutch mounted on the extreme end of the gearbox and fully exposed, a V-shaped member surrounding the clutch, carrying the exposed operating arm pulled by a Bowden cable running under the engine. From the flywheel on the rear of the crankshaft a short splined quill-shaft connects to a long shaft that runs right through the gearbox to the rear-mounted clutch, the drive then going forwards on a concentric sleeve drive into the gearbox and final drive unit.
During practice the short quill-shaft gave trouble, but during the race the new engines and gearboxes ran well. The gearbox has full pressure lubrication on a dry-sump principle, with an oil tank mounted in front of the left rear wheel, while external oil pipes on the gearbox casing direct oil through jets to the gears. The oil tank for the engine dry-sump system is mounted just behind the left front wheel and there is an oil radiator in the nose of the car as on the 907 cars, and, as with the 907 cars, the 908s have a right-hand steering position in the narrow cockpit, and right-hand gear levers, with an air-cooling duct blowing on the lever. Porsche alloy 13-in. wheels are used, with single central hexagon nut fixing, the nut being tightened by a pneumatic impact spanner or a socket spanner and lever of enormous proportions. This type of wheel and fixing is also used on the 910 models, which are now in limited production, some fifteen having already been sold. The 910 has a similar tubular chassis with glass-fibre bonding to the works cars, and uses the 2-litre 6-cylinder engine, with fuel injection. Like the earlier Carrera Six or 906 models the 910 has the steering on the left of the cockpit, but instead of the gull-wing doors of the 906 the 910 has the doors hinged on the forward edge, with a detachable roof panel, in the GT category the Porsches were the lighter and less lavishly trimmed 911T models, with all the permitted homologated modifications to bring them up to 911S standards, complete with alloy wheels and special three choke Weber carburetters.
The Gulf Ford GT40s were Group 4 Sports cars, with the homologated Gurney-Weslake alloy heads and Weber carburetters, the improved porting of the heads increasing the power output, while the stronger bolting-down lands have cured all the Ford V8 head joint troubles. The Belgian-owned car was brand new for the race, with Gurney-Weslake heads and the Piper/Salmon car was new for the B.O.A.C. 500 race, but was fitted with special new front wheels in light alloy.
The two works Alpine Renault V8 cars were the Model A211, the 1967 prototype that first appeared at Montlhéry last October, and the A220, the brand new 1968 car. The A211 has an identical tubular chassis and long-tailed body to the well-proven Le Mans 1½-litre 4-cylinder cars, except that the gauge of the tubing has been increased for extra strength, and the V8 Renault-Gordini engine is coupled to a 5-speed ZE gearbox and not a Porsche gearbox as used on the 1,500 c.c. cars. The new A220 car follows the basic chassis layout of the A211, but is lower and wider, with bigger brake discs, stronger suspension members, and two water radiators, one on each side of the body just behind the doors. The 3-litre V8 engine drives through a 5-speed ZE gearbox, the whole lot mounted behind the cockpit like the A211. There is no mechanism beyond the end of the gearbox, but the tubular chassis frame extends a long way back to carry the tail of the body and the battery is mounted on this tubular structure. Two long exhaust pipes run under the tail to the extremity. The A220 has new alloy wheels with centre hexagon nut-fixing like the Porsches, a system first introduced by Lola, and both Alpines were running on Michelin racing tyres, three types being available; a dry-weather tyre with a smooth surface covered in small holes, a wet/dry tyre with a combination of the hole tread-pattern and a “knobbly” tread and a fully wet tyre with deep “knobbly” tread all over. Suspension on both cars is by coil-spring/damper units and the wheel-carrying uprights are located by double A-brackets, the rear ones having wide bases top and bottom, thus obviating the need for radius rods. While not able to match the speed of the works Porsches and the faster Fords these V8 Alpines have put the French team into a much more competitive position and taken them right out of the tiresome “little blue car” category that has plagued long-distance racing for so long.—D. S. J.