Photograph courtesy of Kenneth Sandelin

Mechanical Specification

History:

Announced at the Frankfurt Motor Show in September 1989, the 348 is the first Ferrari of the 1990. It is the fruit of the last 40 years-plus experience, and expresses the most modern technical concepts of safety and style in the field of automobiles. The most significant features are above all, sporting performance in terms of acceleration, maximum speed, handling in all conditions and the unmistakable Ferrari lines.

As far as the mechanical layout is concerned, the 348 is a two-seater sports car with a longitudinally mid-mounted engine, all round independent suspension and ventilated disc brakes with an anti-locking system. One important design feature is the transverse gearbox (which is represented in the name on the TB and TS versions). All of the solutions adopted - from the geometry of the suspension, to the V-8 3.4-litre engine, to the aerodynamics and the structure of the chassis - have been designed to achieve optimum performance and stem from research and experiments carried out by Ferrari in both the area of GT cars and competition cars.

As far as the design of the bodywork is concerned, Ferrari turned, as usual, to Pininfarina who have a clear view of the requirements when a new car for the "Prancing Horse" stable is being designed. The development of new bodywork is the outcome of research into archetypes of Ferrari production. The 348 has several stylistic themes of the Testarossa, the most obvious of which is the horizontal grille found on the doors which channels the air towards the rear radiator intakes. This demonstrates that on a Ferrari a technical requirement becomes a stylistic theme and nothing is simply there for decoration. Another traditional stylistic element is the view of the front section, which recalls prestigious sporting models of the past such as the 375MM, 196P, 250P, 275LM and the 330 P3 not to mention the extremely current F40.

Accurate preliminary studies and lengthy tests in the wind tunnel have made it possible to combine exclusive lines with extremely efficient aerodynamics with excellent drag co-efficient figures.
The concept behind the design of the chassis for the new vehicle was to obtain a totally resistant structure optimising weight and torsional and flexing resistance combined with the vehicle's features and performance. This result was achieved by using the most advanced construction techniques and the modern development of simple tubular frames and later lattice types which Ferrari have developed for racing cars.

The power unit and the rear suspension are supported by a lattice type tubular sub-frame, which is fixed to the main frame allowing the power unit and the suspension to be easily fitted and checked.
The layout of the mechanical components and main services with the engine mounted on the longitudinal axis, centrally at the rear - the transverse gearbox, the fuel tank in the centre and the water and oil radiators at the side - have made it possible to reduce the polar moment on inertia in favour or manoeuvrability.
The suspension has been designed with the requirements of a high performance car in mind. The suspension arms, which form a parallelogram for each suspension are made from pressed steel and the steering knuckles are made of forged aluminium. This means a reduction in the unsprung weight.

In order to improve road holding wide tyres are fitted on 17" wheel rims and gas shock absorbers are utilised. The geometry of the front suspension has been designed with the "anti-dive" function in mind and the timing of the front and rear suspension frequency is a product of Ferrari's experience in this field.

The extremely low centre of gravity also enhances road-holding qualities. It has been made possible thanks to the new design of the power unit which has allowed the mass of the unit to be lowered by 13cm compared with the transverse version.
The braking system reflects the experiences and developments with racing cars. The callipers are made of aluminium with twin cylinders, which are a new feature in series produced vehicles. Aluminium brake callipers are lighter (and therefore assist the reduction of the unsprung weight) and increase the dissipation of thermal energy, which improves the operation of the braking system. The front discs have a diameter of 300mm and are 28mm thick; the rear brakes (which incorporate the handbrake device) have a diameter of 305mm and are 24mm thick. The servo-assisted braking system is also fitted with an anti-locking device.

The 90° V-8 engine is longitudinally mid-mounted. It has a capacity of 3405cc bore and stroke 85 x 75mm and the compression ratio is 10.4:1. The sophisticated design of the combustion chamber with four valves with the spark plug at the centre has made it possible to optimise volumetric filling and thermo-dynamic efficiency. The engine has a power output of 221kW (300bhp) at 7200rpm and a maximum torque of 323Nm (33kgm) at 4200rpm. The specific power, which is close to 90hp per litre, is a significant result. Amongst the notable technical features, is the construction of the cylinder head and block from light alloy with steel liners coated in Nicasil, (directly in contact with the coolant), the crankshaft on five main bearing supports with the crank at 180°, the tappets with clearance adjustment pads, the dry sump lubrication with an 8-litre lubrication reservoir, copper radiators with two thermostatically controlled fans and an expansion tank and thermostat. The electronic management of both the ignition and injection is by a double-integrated Bosch Motronic M2.7 system, which effectively controls each bank of cylinders separately. The system incorporates a hot wire device for measuring the mass of inducted air. The inlet duct geometry provides variable resonance characteristics.
Each bank of cylinders has a manifold and an airflow metre and two systems can function independently; however, at the centre of the ducts there is a connecting passage closed by a butterfly valve whose opening is determined by a command sent by the electronic unit running the entire system.

For each of the two positions (butterfly valve open or closed) there is a corresponding different arrangement for the ducts, which varies according to the engine speed. The particular shape of the intake trumpets (two per cylinder), located inside the manifolds contributes to improving the dynamic flows.

The ignition is of the static advance type with advance curves stored in the memory of the electronic control unit. For each row of four cylinders there is a high-tension unit with two coils, each with twin outlets for supplying the four spark plugs. At the end of the 1974 season Ferrari introduced a new F1 single seater with the identification letter 312T. As in previous models the number part was made up of a first figure which represented the cubic capacity (3-litres) and the other two figures standing for the cylinders (12).

The novelty was the letter "t" standing for the word "trasversale" which stood for a completely new transmission where the conical idler gear was positioned at the intake for the gearbox, which had become transverse, coining a new type. Although transverse gearboxes had already been used in the past (for example on the Ferrari D50 derived from the Lancia of Jano) the one fitted on the 312T was the first time the transverse transmission formed a block with the central engine. The single seater "T" series cars had a very successful racing career: Niki Lauda won the World Championship title in 1975 and 1977 and Jody Scheckter won it in 1979; the car won the Manufacturer's Championship in 1975, 1976, 1977 and 1979.
The transmission of the power to the wheels takes place by means of a completely new system, located on the transverse gearbox. The engine flywheel is no longer at the end of the crankshaft but has been moved in relation to the clutch, which projects at the rear and is connected to the engine by a shaft, which crosses the gearbox. The diameter of the clutch plates is 8-1/2".
The flywheel is of the "bimass" type with an internal oscillation damper. The dry clutch is hydraulically operated and at the clutch outlet there is a cylindrical idler gear and then a 90° conical idler gear, which transmits the power to the gearbox. The gearbox with five forward speeds and reverse has new type synchronisers and is connected to the differential by a cylindrical idler gear. The differential is of the limited slip type calibrated at 40%.

Ferrari have mounted the rear clutch outside the gearbox since 1960 with the design of a new single seater for Formula 2 racing with a six-cylinder 65° V formation 1500cc engine which became the F1 in 1961. The American Phil Hill won the World Championship title in 1961 with this car. The aim of this solution was two-fold: on the one hand it made this part of the transmission, which in racing cars is subject to a great deal of stress, very accessible, thereby facilitating checking and repairs; on the other hand, it greatly improve cooling and therefore endurance.
The external control was carried out by means of a central actuator. Currently on the 348 a hydraulically operated ring piston is used instead which has the merit of making the clutch operation extremely light. The 348 is capable of 0-100kph in 5.6 seconds and has a top speed in excess of 275kph (172mph).

Taken from 'Ferrari Market Letter'
Volume 14 No 19, 16th September 1989.