Formula One Facets
The Gearbox
The name of Mike Hewland and his engineering company are well known throughout the World for racing car gearboxes and final-drive units. They make racing gearboxes for everything from USAC Indianapolis cars to Formula Ford and apart from Ferrari the whole of the Formula One firmament rely on the Maidenhead concern in some way or another. At one time most constructors took a basic Hewland gearbox/final drive unit and designed the back end of their Formula One car around this. As the technical pace of Formula One speeded up and as more money became available, design staff increased and the basic Hewland transmission no longer fitted into the designs of the major teams. They all wanted small variations on the theme, to fit in with new ideas, and it was impossible for Hewland to market a Formula One gearbox that would satisfy four or five different designers. They were all looking for ways of improving on the basic gearbox, and were all searching for increased reliability and all had their own ideas on lubrication.
Today, although nearly everyone uses a Hewland based transmission the individual variations are most interesting. The first team to break away into a new field was McLaren who designed a 6-speed gear-cluster and selector mechanism to fit into the standard 5-speed Hewland casting. They still get their own internals made, with their own design of crownwheel and pinion, their own design of shafts and so on. Naturally they designed their own dry-sump oiling system to go with their 6-speed cluster and still run their own ideas on lubrication. Outwardly the back end of a McLaren M26 looks to have an orthodox Hewland gearbox and final-drive unit, but internally it is very much McLaren design.
Another designer who broke away from the conventional Hewland package was Gordon Murray, when he designed the Brabham with the Alfa Romeo flat-12 engine. With Alfa Romeo facilities available Murray was soon into the design of a new transmission more suited to the Alfa Romeo engine and the rear end of the car. Today the transmission of the Brabham BT46 cars uses Hewland gears, bearings, oil seals and selectors but they are fitted into a casing made specially for the car. Murray uses his own design of crown-wheel and pinion, his own gearbox shafts, his own oiling system and other detail refinements to assist in efficiency and reliability. Naturally, each designer has his own ideas about the internals of a gearbox and most were reluctant to go into details, preferring to keep their secrets to themselves.
Last year, and early this season, Team Lotus were trying out their own design of gearbox, manufactured for them by the German Getrag company. This is an all-new system of gear-changing that Lotus have been working on for some time, and while it shows good promise it has had various troubles. While development continued in the experimental department of Lotus the 79 was drastically modified to take a Hewland transmission. Although Lotus buy complete gearboxes from Hewland they discard a lot of the bits and replace them with their own parts. The side plates for the differential housing are changed, to fit into the 79 rear end design; the differential itself is of Lotus design, and the lubrication is entirely Lotus, utilising a dry-sump system, as most other designs do. Hewland gear clusters are retained, as are the crown-wheels and pinions, and all bearings, oil seals and selectors. Once again there were numerous internal modifications mentioned, but not for publication, all in the eternal search for better reliability. It is more than likely that the Lotus Getrag gearbox will re-appear next year on the Lotus 80.
The Tyrrell team use what is basically a Hewland gearbox and final drive, but they purchase all the parts and assemble the whole thing in their own factory. Their gearbox specialist reckons to spend a week on the assembly of a complete transmission. Many of the Hewland components are modified at Tyrrell’s, in line with their own ideas, and they use their own system of dry-sump lubrication.
It is a similar story with the rest of the teams, the days of buying a standard Hewland gearbox and attaching it to a Cosworth engine to form the mechanical aggregate of your Formula One car are long gone. Each team has its own ideas about gearbox internals or where and how the oil should flow. What Hewland do for Formula One is to supply the basic components. This they do for Renault and Ligier, as well as all the British based teams.
When next you read of someone retiring with gearbox trouble bear in mind that while it may look like a standard Hewland Formula One gearbox from outside, it could well have been “got at” by the team’s designer. Whether the failure is due to modifications made by the team, or due to Hewland Engineering is hard to discover, but Hewlands have to “carry-the-can” publicly. If a Ferrari retires with gearbox trouble we know exactly where the blame lies. – D.S.J.
R5-turbo
The turbocharger really is spreading its net far and wide these days. The provision of an exhaust system turbine wheel to provide extra power without the power loss of the previously popular supercharger has now become such an accepted facet of competition that Renault have actually “gone the whole way” and produced a parody of a Renault 5 for display and possible competition purposes.
It has a centrally mounted 1.4-litre Renault V6 with a turbocharger of the type that won Le Mans, we are told (though we have not seen the engine installation). We are also informed that it is a logical extension of Renault’s turbo thinking in competition. First sports cars, then Formula One and now the Renault 5!
Apparently the company are seriously considering making 50 such beasts and using them for rallying Group 4 form. Readers of the French press are reminded that the R5 nearly won the 1978 Monte Carlo Rallye, so this ferocious combination should provide messrs. Frequelin and Ragnotti with an almost certain win in 1980.
The example produced for the Paris Show early in October was a beautifully finished machine with all the cockpit fittings of a road car. The exterior bodywork features a full width front spoiler, wheel arch extensions, and the smoothly incorporated entry and venting necessary for what must be a side-radiator installation to cool the mid-engine.
Apparently the factory engineers at Renault Sport enjoy nothing more than travelling at over 124 m.p.h. on the autoroutes with the device. The possibilities on a subsequent court appearance must be entertaining … “but it’s only a Renault 5 your honour … !”