Technical View, Countach LP400

This is the first Lamborghini Countach, LP400

Paolo Stanzani
Chief engineer Paolo Stanzani might not be as ingenious as his ex-boss Dallara, but he gained priceless experience in developing racing cars when he was working for Maserati, then learned a lot from Dallara after joining Lamborghini. Countach was his first car started from a clean sheet. In particular, the chassis and drivetrain arrangement was his idea. It is this car that made his name so famous in sports car industry, so famous that many years later when Romano Artioli wanted to create Bugatti EB110, the first name in his mind was Paolo Stanzani.

Engine
Since 1963, Lamborghini had the best V12 in the world. Its 3.5 litres V12 has double camshafts in each bank of cylinders, not only offered significant power advantage over Ferrari's single cam V12s, it was also praised for smoothness and responsiveness. Originally designed by ex-Ferrari engineer Giotto Bizzarrini, this V12 gained capacity, compression ratio and power in the following years. While the development of Countach started, the V12 was already upgraded to 385 hp from 3.9 litres capacity, which powered the last and fastest Miura, P400SV. What could be better as the starting point of Countach's engine ?

Stanzani originally wanted to increase the capacity to 5 litres to provide the power needed for 200 mph top speed. As publicised in the LP500 prototype in the 1971 Geneva show, the " imagined " V12 had 4,971 c.c. and capable of as much as 440 hp. However, there were serious development problems ( and perhaps limited by the budget ) so that it was soon discarded. Instead, Miura's 3929c.c. unit was adopted, with some modification of course.

The V12 is extremely "over-square" to boost power - 82 mm bore versus 62 mm stroke. Aluminium alloy head and block. Dohc per bank driving 2 valves per cylinder. Compression ratio is 10.5 : 1. Dry sump lubrication ..... all these were the most spectacular specification in then. The peak power is 375 hp, occurs at sky-high 8,000 rpm if you believe Lamborghini's claim ( usually less trustable than Porsche ). Peak torque is 268 lbft at 5,000 rpm. Don't think it must be very peaky, in fact road testers praised its good manner.

Unlike Miura, the V12 is positioned in north-south direction for better cooling. The transmission, now no longer incorporated with the engine sump, is placed in front of the engine for better weight distribution.

Drivetrain
This is the most extraordinary part of Countach. Stanzani knew the big V12 would inevitably making the rear end heavier than the front, thus result in excessive oversteer and difficult handling. To make Countach more balanced, he created a new idea - put the gearbox and clutch in front of the engine, that is, in the wide central tunnel between the driver and the passenger. There is another advantage : the linkage between shifter and gearbox is vastly shortened so that gear shift operation becomes more precise and effortless.

Nevertheless, there are some draw back. The output from the gearbox is transmitted back to the rear axle via a drive shaft placing underneath the engine, inside the sump. Inevitably, the engine has to be raised for a few inches to accommodate the drive shaft. As a result, the center of gravity is raised, too.

As the engine sat higher, to compensate for the loss of rear vision the carburettors were repositioned to horizontal. Less ideal breathing account for the 10 horsepower loss compare with Miura SV.

Ferrari's boxer engine also got similar problem. Since the 12 cylinders engine was too long, it simply put the gearbox underneath the engine. As a result, the engine was placed even higher than Countach although it was a flat engine. Other mid-engine 12 cylinders cars chose to install the gearbox behind the engine and rear axle. This preserved the low centre of gravity, but could not help balancing front and rear weight. No matter which layout, there are always some problems exist.

Chassis and body
Having experience of tubular space frame technology in designing the Maserati Tipo 61 "Birdcage" race car, Stanzani adopted tubular space frame construction in Countach. Although it was quite complex and costly, high rigidity and lightness were guaranteed. The chassis also acted as supports for the body panels, which were made of hand-beaten light aluminium. Nearly the whole underbody, except the chassis, was made of glass fiber.

At the time when carbon fiber was not yet invented, Countach undoubtedly did everything to save weight.

In order to enhance stability in high speed cornering, the body was made wide and low. Wider body did not reflect in cabin room, because the space frames created a wide sill between the door and the seat. Ultra-low body was achieved by installing the thin seats directly to the floor, though I suspect its effectiveness in lowering the overall centre of gravity. It couldn't help much the drag too, because any reduction in frontal area is nothing compare with the awful drag coefficient in excess of 0.40.

As expected for a supercar, Countach employed double wishbones suspensions in all corners.


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