Turbo-Charging in Formula One

Ferrari and Alfa Romeo 

IT IS now three years since the first turbo-charged 1 1/2-litre Renault appeared in Formula One and to begin with a lot of people scoffed at the idea of a boosted 1 1/2-litre engine being able to match the power of an unblown 3-litre engine. Renault do not make any wild claims for their little V6 engine, relying on its performance to speak for itself. In the last three Grand Prix races the Renaults have proved conclusively that they have a lot more horsepower than Ferrari, Alfa Romeo or Cosworth 3-litre engines, The Ferrari engineers have been working on a turbo-charged 1 1/2-litre V6 engine all season and it made its first public appearance at Imola. The four-camshaft V6 engine has an angle of 120-degrees, with the exhaust camshafts inside the vee and the inlets outside. This allows short exhaust pipes from each bank of three cylinders to feed straight into turbines mounted above the engine, with the compressors forward of the turbines, so that you have the two compressors immediately behind the fuel tank. The outlets from the turbines run rearwards into pressure-release valves and there are short tail pipes just ahead of the final-drive unit. Air intakes for the compressors are on each side of the fuel tank and the compressed air feeds out each side into inter-coolers mounted in the side-pods. From under these coolers the inlet manifold runs rearwards into collector manifolds with individual inlet pipes running upwards under the cylinder heads. Apart from being a compact arrangement, with all the exhaust pipes and the turbo-charger units in the vee of the engine it leaves the under-side of the power unit free from piping of any sort.

The transverse-shaft gearbox is much more compact than on the T5 Ferrari and is still ahead of the final-drive unit. Rear brakes are outboard, using twin calipers to each disc and the coil spring suspension units are inboard and operated by rocker arms. Front suspension follows similar principles, with rocker arms operating inboard coil-spring units, but the tubular structure carrying these rocker arms looks a bit crude, as does the cockpit structure and the footwell box of riveted aluminium sheet.

Designated the Ferrari F1-126C and carrying on the chassis serial numbers from the T5, the car that appeared at Imola was number 049, and b.h.p was mentioned as being "about 550" using German KKK turbo-charger units. Enzo Ferrari insists that the C indicates Competzione, not Compressore.

Alfa Romeo have been bench-testing their turbo-charged 1 1/2-litre engine with satisfactory results and it is now ready to be installed in a test-chassis and run on their private track at Ballocco. It is a V8 cylinder layout, with the two banks at 90-degrees and has a bore and stroke of 74 x 43.5 mm with a displacement of 1,496.7 c.c. This tiny stroke allows a maximum of 11,600 r.p.m and the two turbo-chargers boost the power output to a quoted 550 bhp. All this on 98-100 octane pump petrol. With a misty look into the past Alfa Romeo called this new engine the Tipo 158, indicating 1.5-litres 8 cylinders. It is a very neat and compact looking engine with alloy block and alloy heads of conventional four-camshaft layout with single central sparking plugs. A jack-shaft in the vee drives the SPICA fuel-injection pump, mounted towards the rear, and at the front of the engine this shaft drives a triangular-run toothed rubber belt drive which drives a water pump mounted low down on the right of the crankcase and the oil pumps on the left of the crankcase, as on a Cosworth DFV. On each side, the four exhaust pipes feed into a KKK (Kuhnle, Kopp & Kausch) turbo-charger which then exhausts rearwards alongside the gearbox, with the smaller exhaust pipe from the waste-gate above. The compressor is outboard of the turbine, taking in air from the side and feeding it forwards to an intercooler and then into a collector tube above the engine with four inlet pipes running downwards to the inlet ports on each cylinder head. Right and left systems are identical. An ignition distributor is driven off the rear of the right-hand inlet camshaft and an alternator off the rear of the left-hand inlet camshaft.

With turbo-charged engines from Ferrari and Alfa Romeo ready for 1981 we shall enter on a new era of sound. The advent of the flat-12 Ferrari caused the passing of the musical high-pitched scream of Ferrari V12 engines, lamented by true Ferrari enthusiasts and now the harsh bark of the flat-12 Ferrari engines will give way to an entirely new sound from the turbo-charged V6 engine. Alfa Romeo's rather raucous exhaust note from their flat-12 and their V12 will give way to the comparatively woolly sound of a turbo-charged V8. The 1980's are certainly heralding a new era in Grand Prix racing. — D.S. J.