British Grand Prix Preview -- Ilmor

Reliability and Precision

Which country has made the greatest contribution to the development of the high-performance or racing automobile? France? Great Britain? Italy? Germany? There is no single, certain answer; any of these countries might qualify. But one could also make a strong case for Switzerland even though very few cars of any type have ever been made there. From the first years of this century, Swiss engineers, generally working abroad, have displayed a singular genius and remarkable aptitude in the art of automotive design.

The Geneva born engineer, Ernest Henry, set the pattern for all high-performance motors down to the present day with his DOHC 16-valve Peugeot design. And another Swiss, Alfred Buchi, invented the turbo-supercharger. The modern sports car can be traced back to the Alfonso XIII Hispano-Suiza design of Marc Birkigt, and another outstanding Swiss engineer, George Roesch, continued development of the sports car line with his Talbot designs of the late 1920s and early 1930s.

In more recent times, Swiss born and trained automotive engineers have continued to show their skills. The H(igh) E(fficiency) cylinder heads found on Jaguar V12 engines were invented by Michael May, a native of Zurich, and he was also probably the first to mount a wing on a racing car in order to get downforce. And today, another engineer of Swiss origin, Mario Illien, is beginning to make his mark on the racing world. Along with partner Paul Morgan, he founded Ilmor Engineering, the company which designed and makes the immensely successful Indy/CART engines that carry the nameplate of Chevrolet, a firm founded by Swiss born engineers.

Now in his early forties, Illien studied engineering at Biel before going to work at Mowag, a diesel engine and heavy vehicle manufacturer. He became involved in motor racing through working with the late Grand Prix driver, Jo Bonnier, for whom he designed a 16-valve cylinder head for the Chrysler/ROC Formula 2 engine. In 1979, Illien moved on to Cosworth where his skills were honed chiefly on the DFY Formula One motor and the Sierra 16-valve engine. Paul Morgan was already at Cosworth having come to the Northamptonshire firm in the early 1970s after graduating from Aston University. Morgan worked on various projects at Cosworth, including the 24-valve 3.4-litre Capri V6 and the two-cylinder 750cc Norton motorcycle engine. Of greater importance for the future was Morgan’s early involvement in Cosworth’s programme to turbocharge a 2.65-litre of the DFV for Indy/CART racing.

While at Cosworth, Illien and Morgan became friends through a shared interest in racing engine design and manufacture. They also had in common the ambition of wishing to start their own company. From frequent visits to America, Morgan knew there was a market for a new engine specifically designed for Indy/CART racing. To get an Indy/CART engine project (and their prospective company) off the ground, Morgan and Illien recognized that they would need a sponsor and turned to Roger Penske for support. For over thirty years, Penske’s successful involvement in racing in America has been characterized by two features. First of all, his cars usually have had some — often technical — advantage over the competition; and, secondly, from the days of the Zerex special, he has been quick to recognize and exploit opportunities of both a racing and commercial nature.

Morgan and Illien made their approach at just the right time. By 1982, almost all Indy/CART racing cars were powered by the Cosworth DFX. Though a superb engine, the DFX basically was a modification of a design that was almost twenty years old. Secondly, at that time, American racing authorities wished to promote competition; they were prepared to freeze development of the DFX which would give potential new engines a chance to become established. Penske could see the advantages of a new engine using the latest technology and designed from the outset specifically for CART/Indy racing. A new engine could be smaller and lighter than the DFX and, hopefully, more powerful as well. He agreed to finance development and find long-term sponsorship for the project. After resigning from Cosworth, Illien and Morgan set up llmor Engineering Limited. They started with a small but very well-equipped factory on a new industrial estate in Brixworth, a village a few miles north of Northampton.

Ilmor’s first product was the compact (569mm long) 265A Indy/CART engine, a four-cam 90° V8 of 2.65-litres (88mm x 54.4mm). Like almost all racing engines these days, each cylinder has a central spark plug and four valves, the latter being set at the relatively narrow included angle of 24°. Naturally, the 265A appeared similar to Cosworth’s DFX and DFY, and the churlish or jealous went on to suggest that Ilmor’s engine was little more than a Cosworth by another name. In fact, the 265A is very different and more original than one might expect, and Illien and Morgan have many admirers amongst the engineering fraternity. Features like the camshaft drive mechanism and the crankcase/oil scavenging system have been praised and copied. Ilmor’s critics might also have remembered that Illien is of Swiss origin and that the long and continuing success of Switzerland’s leading industry is due in part to the ability of Swiss etablisseurs to learn quickly by imitation and adaption and yet still be capable of real innovation.

Development during the first year or so was focused on sorting out teething troubles of the 265A which were mainly related to crankshaft balance. Early versions of the engine were red-lined at 11,400 rpm, though it had been stressed at the design stage to run more than 12,600 rpm. Peak power is now about 720 bhp, and from the first the 265A has never been short of power. Over the years, the engine has been improved mainly through the use of better materials and higher quality in manufacturing. As a result of such changes, the rate of failure during races has been reduced to less than 5%, a very low figure by any standard.

The engine won its first race in 1987, and since then the company has never looked back, winning championship after championship. So far this year, Ilmor’s engine has won every race on the CART circuit, including the Indianapolis 500 where the top five cars were powered by Ilmor engines. The 265A has not only superseded the once dominant Cosworth DFX/DFS: it has seen off a very serious threat from Porsche, a far larger and more experienced company, and to date has not been greatly troubled by the Alfa Romeo challenge, another firm with more racing experience and far greater resources.

How does one account for such extraordinary success? Good timing, good engineering, and good manufacturing practice are the answers. The first might be fortuitous, but the last two derive directly from the design and manufacturing experience and philosophy of Illien and Morgan. The qualitative approach to manufacture is most evident in the facilities which the company’s founders have created. The Brixworth works seems more like a fabrique of the Jura or some aerospace factory than the traditional machine shop of the Midlands. Metal shavings do not lie about, nor does oil stain the floor; tool-proud craftsmen see that work is done well and neatly. The factory is also unusually quiet. People go about their business in an orderly, measured way with industriousness and tranquillity somehow combined. Everything seems to run, dare one use the simile, like clockwork.

The distinctive Ilmor philosophy is evident in the factory building itself. It was designed to Illien and Morgan’s specifications and reveals something of the personalities of the men who created the company. Like other, similar engine R & D firms, there are the usual fully-instrumented test-beds, but these test-beds are different; they perform two functions. Ilmor’s dynamometers provide information on engines in the normal way. However, in the course of test runs a considerable amount of heat is produced. Usually this heat is vented to the atmosphere. Not so at Ilmor; waste heat is used to warm the factory building. A single engine running for a few hours on the test-bed produces enough waste heat to keep Ilmor’s facilities at a comfortable temperature for an entire day. Economy. Efficiency. Intelligence. Responsibility

One also sees at Ilmor other values usually associated with the Swiss: diligence and commitment and a work ethic that is both personal and collective. Reliability and precision in manufacture are much prized by the Swiss and given similar regard at Ilmor. The machine tools and test instruments of the firm give evidence of an overriding concern with quality. As a matter of policy, all machine tools are purchased from new and are the best that money can buy (some cost £250,000 or more). Second-hand or re-conditioned machine tools can be acquired for much less, but used machinery may be worn and wear can lead to inaccurately made parts, and inaccurately made parts may cause engine failure. This year, even the machine shops will be air-conditioned so that all machining can be done at constant temperature, thereby ensuring that tolerances will be even tighter and more consistent.

Major castings like blocks and heads still come from outside suppliers, as do the forgings. As a general principle, too heavy a reliance on outside suppliers can be risky. Problems of communication and lack of direct control can result in the occasional flawed or defective component. Secondly, racing engine manufacturers require short lead times; new parts are needed in days and not months, as is customary in the foundry and forging business. Orders from racing engine companies are usually small, both in numbers and value, but racing demands components of the highest quality. Morgan deals with these potential problems by selecting sub-contactors carefully. In particular, he looks for relatively small firms able to recognize that there are long-term and indirect gains from involvement in a high technology project, even though initial orders from Ilmor may not be numerous or exceptionally lucrative. Sub-contractors have found working for Ilmor attractive for it is company policy that invoices are paid promptly, a practice which ensures good service in the future.

According to Morgan, who looks after the production engineering side of the business at Ilimor, metal heat treatments are another potential problem and a major cause of engine failure. Firms like Ilmor need large and sophisticated quality control sections to monitor treated or bought-in parts. In the end, the most effective way to guarantee quality is to do the work on premises, though that course may not always be economical. At Ilmor, more and more work is being brought in-house. For example, even the electrical looms are now made at Brixworth as well as being checked on special machinery after manufacture and then later at the race track.

Until this year, the company has had only one product, but now Ilmor have made a second racing engine, the LH-10, which took about 18 months to develop from the initial concept stage through to its first test run in a Leyton House Grand Prix car. The LH-10 is a 72° V10 engine of 3.5 litres capacity. The main engine castings are made of heat-treated aluminium alloy. The crankshaft and connecting rods are machined from an alloy steel. The deep-sided block has six main bearings of plain metal type and the four camshafts (two per bank) are driven by a train of spur gears off the front of the engine. The position of this gear train marks a departure for Ilmor. The cams on the 265A were driven from the rear of the crankshaft, as they are on the Honda and Judd V10s.

So far, few figures relating to the new engine have been released by the company, except overall length and weight. The LH-10 is only 593.5mm long which makes it the shortest multi-cylinder engine in Formula One. Even the V8 Cosworth Ford HB engine (595mm) is slightly longer, and only the older Judd V8 is shorter. Compactness in general was one of the main design criteria, and the overall envelope of the engine is probably the smallest of any Grand Prix engine. The engine looks extremely narrow, in part because the cam covers are only a few inches across. It is also a light engine, weighing approximately 122kg. Weight discipline was pursued rigorously throughout the design process. Illien takes delight in reminding his partner that the final product has turned out to be within one kilogram of the calculated design weight. In talking about the LH-10, Illien indicates that no single factor has been allowed to dominate the design process. The engine has been seen as a whole; size, weight, horsepower, torque, fuel economy, reliability, etc, have all been kept in balance from the first, conceptual stage and throughout later detailed design phases. The piston engine has been around for a hundred years, as Illien observes, and most improvements these days now come from attention to detail and from reducing internal losses. The latter assume greater importance as engine speeds go up. As rpm increases, the law of diminishing returns becomes apparent; an ever-greater proportion of power is lost to friction, oil drag, and pumping until any potential power gain from higher speed is cancelled out. Ultimately, as Illien admits, any formula based on cylinder capacity will result in an emphasis on high engine speed, and the LH-10 has been designed for high rpm. It is already running to 13,400 rpm and more may be expected. But as Illien and Morgan state, it is relatively easy to make a high-revving engine, but what really matters in racing is the amount of power available throughout the rpm band used by drivers and not that produced only at peak rpm.

Basically there are two ways of achieving power, though a surplus of one will not make up for a surfeit of the other. Some engineers seek high power through deep breathing by using broad bores, short strokes, and maximum valve opening area. Others put more emphasis on maximizing the efficiency of the porting and combustion. Judged by the 265A and from what can be learned of the new LH-10, it appears that Ilmor lean toward the latter design philosophy. A range of information including the most obvious the shortness of the engine, indicates that piston area has not been a primary objective. The cylinders of the LH-10 are probably 90mm or less in diameter. Secondly, the narrowness of cylinder heads suggests that maximum valve area has also not been a design objective. Instead, effort has been directed more toward increasing flow through available valve opening area, and much attention has been paid to piston and combustion chamber shape. Illien has designed an exceptionally compact chamber of regular shape so that the fuel/air mixture will ignite easily and the flame front travel quickly and uniformly across the chamber. A compression ratio of between 12.1 and 13.1 is used.

Because the heads are narrow, it has been suggested that the LH-10 has absolutely vertical valves as were used on the 3-litre V12 Maserati engine of circa 1967 or on the Rolls-Royce Merlin aero-engine whose four valves per cylinder were parallel. Illien expresses considerable admiration for the Merlin design, though Morgan suggests (with tongue in cheek) that it had one defect — two cylinders too many. Heron head designs may appear attractive, but as Illien notes, piston weights are usually higher with such a layout. So the four valves of the LH-10 are presumably placed at an extremely narrow included angle (16-18° at a guess) with the combustion chamber comprising of the space in the head between the valve faces and the low crown pistons into which indentations for valve clearance have been carefully blended.

Like its predecessor, the LH-10 has been financed by Roger Penske, at least through the initial development stage, though it is expected that a sponsor will fund it over the long term. The experience of Indy/CART racing has made Ilmor wary of expecting instant success from their new Grand Prix engine, most brand new engines have some teething troubles. Early running of the LH-10 has shown minor problems, but these the company hope to rectify by mid-season.

Will the LH-10 be successful? The exceptional lightness and compactness of the engine should give a chassis designer some advantage, but at this stage it is too early to say whether the llmor will prove competitive in terms of power and reliability. Considering the quality and depth of competition in Formula One these days, it is too much to anticipate early victories or the sort of domination achieved by the 265A in CART/Indy racing. Illien and Morgan are aware of the tough nature of Formula One. Indeed, the need to meet the competition has led Illien, as he admits, to take more risks with the LH-10 than he did when designing the V8 Indy/CART engine. Ilmor hope the LH-10 will soon achieve reliability; then incremental development can concentrate on increasing the power of the unit.

Ilmor’s task will not be easy, for it is not a large firm with unlimited resources. Currently, about 109 employees are on the pay roll. Inventive and skilled staff are not a problem; nor is quality of manufacture. Ilmor is well endowed in these departments. But independent firms, like Ilmor, are at a disadvantage, compared to much larger companies like Honda, Ferrari/Fiat, Renault, etc, in that they do not have the scientists or technicians, the laboratory facilities, and the money to undertake extensive basic research and development, particularly in the area of materials and electronics. A firm like Ilmor must often work with what is currently and commercially available from its suppliers.

To a lesser degree, this is true in areas like computer-aided design. Only the major automotive manufacturers have the super-computers and software needed to apply computational fluid dynamics to optimise gas flows and combustion chamber design. A firm like Ilmor is not equipped to undertake research programmes of that sort to improve its engines. Instead, Ilmor must make maximum use of its most valuable resource; the intelligence and experience of the designers. A few minutes of careful cogitation may provide more useful answers than hours of costly computer analysis.

Everything one sees about Ilmor suggests care and thoughtfulness, not simply in how an engine is designed and made but also in the way the firm operates. Like any good partnership, Illien and Morgan work together. They are able to communicate easily, both are qualified engineers, and are able to trust each other’s judgement. Each has assumed special areas of responsibility. Illien takes the lead on design while Morgan oversees the manufacturing side. Work on the factory floor progresses in an orderly, though energetic way. Ilmor Engineering may be located in Northamptonshire and the workforce is overwhelmingly British, but from the seriousness and sense of purpose that one sees in the company, one might think it a Swiss establishment. And as in the Swiss watchmaking industry, there is at Ilmor a similar, deep commitment from top to bottom to see that the company makes the best in the world. — DDH