The greatest engine in Formula 1 history

"I left Ferrari at the end of 1969," Chris Amon said, "and always regretted it, but at the time it seemed like something I had to do. The cars always handled well, but the V12 sounded way more powerful than it was, and you could never convince the Italians of that.

"At Brands Hatch in 1968, for example, I started from the front row, and finished second after a long fight with Jo Siffert's Lotus. Mauro Forghieri and the others were annoyed I didn't win, but I was absolutely balls out the whole way. It was the same old story - out of the slow corners the Ferrari was simply blown off by the Cosworth.

"The following year was even worse, but we had the flat-12 coming for 1970, and I was impressed by it in testing. Trouble was, it kept breaking after only a few laps, and one day I just thought, 'I've had it - I've got to have a DFV.'"

Like 'D-type' and '250F', 'DFV' has gone into the lexicon of motor racing: nothing else need be said. Yet when I think back now to the mid-1960s, when it became known that Ford was to have a grand prix engine, I was horrified, and so were all my friends. Ford - in Formula 1?

Half a century on it seems barely credible that we reacted that way, for was not Ford already deeply involved in motor racing, not least with a very serious sportscar programme? Having failed to buy Ferrari, the US company had resolved to take on Enzo at Le Mans, and in 1966 it beat him. As well as that, everyone was accustomed to the sublime sight of Jimmy Clark flinging a Ford Lotus Cortina around Silverstone or Oulton Park - even if we preferred to think of it as simply a 'Lotus Cortina'.

Formula 1, though, was a different matter - sacrosanct, if you like. Exclusive. Somehow 'Ford' didn't belong at the very summit of the sport, as Jackie Stewart, for countless years synonymous with the company, remembers.

"Cosworth had been working with Ford engines for a long time, in the junior formulas and saloon cars and so on, and Keith Duckworth and Mike Costin had also worked for years with Colin Chapman - but none of that registered with the doctor or lawyer, whereas Formula 1 did. The times were very different then, and - however you want to put it - what the DFV did was allow Ford to come from being 'a working man's car' to something a doctor or a lawyer might drive.

"Winning Le Mans went a long way to transforming the image of the company, and winning grands prix with the DFV took it a stage further - it sort of made Ford socially acceptable. Trust me, the Ford Dealer Group knew very well that racing sold cars."

Had Coventry-Climax, for so long the mainstay of British grand prix teams, opted to build an engine for the new three-litre Formula 1 in 1966, the DFV might never have seen the light of day, but it decided otherwise, at which point Chapman proposed that Duckworth design an engine, and he would find the money for it. It could have been an 'Aston Martin' or even an 'Esso', but ultimately both companies turned it down, at which point Chapman put the idea to Walter Hayes, Ford's UK head of PR.

"Without Walter," says Stewart, "the DFV would never have happened, simple as that. He agreed in principle to the designing and building of the engine, but of course it needed Henry Ford II to commit to it, and he convinced him to do that."

So it was that the project went ahead, a simple document - written by Duckworth, signed by Ford - agreeing to the provision of £100,000 to Cosworth: £75,000 for the F1 DFV, £25,000 for the Formula 2 FVA. It was also decided that Lotus would have the DFV exclusively for one year, 1967, after which it would be sold to anyone who wanted it. Plenty did.

Mario Illien, who worked at Cosworth in the 1970s and remembers Duckworth as a genius, describes the DFV as "a relatively simple engine, with a fantastic cylinder head, four valves per cylinder, good combustion - mechanically just a very sensible piece of engineering, and torsionally very stiff because it was designed from the start to be used as a fully stressed member, integrated into the Lotus 49 as a part of the chassis. At the time that was a novel idea."

The new car and engine appeared for the first time at the Dutch Grand Prix in 1967. Graham Hill had given it a shakedown at Snetterton, but Clark, then living in Parisian tax exile, had not so much as seen the 49 until he arrived at Zandvoort.

The bare facts of the race are that Hill took pole position, and led before retiring, and that Clark won. It was a little like Reims in 1954, when Mercedes returned to racing, and suddenly every other F1 car was obsolete. The 49, in its early guise, was by no means an easy car to drive, and neither was the power delivery of the DFV as smooth as Clark and Hill might have wished. But these were shortcomings great drivers could surmount: plainly the lovechild of Chapman and Duckworth was instantly quicker than anything else.

Small and light, the DFV gave around 400bhp, a figure approached only by the prodigiously heavy Honda V12. A Ferrari V12 of the time produced around 370bhp, but sat in a weighty car, and the same was true of the Eagle-Weslake and the Cooper-Maserati. While Brabham's Repco V8 was worth little more than 340bhp, in terms of power-to-weight ratio it was probably closer to the Lotus than anything else, and on handling had a definite edge.

Part of the problem with the 49 stemmed from a combination of the early DFV's characteristics and the fact that Lotus was using what was essentially a fixed-ratio gearbox from ZF. It wasn't that ratios could not be changed, more that it was a complex and hugely time-consuming task, and therefore the drivers invariably had to make do.

"The DFV is much more powerful than any Formula 1 engine I've driven before," Clark commented. "That's not a problem in itself - except that it comes in with a bang at 6500 revs. Alright, ideally we shouldn't be down at those revs, but sometimes - because we can't change gear ratios - it's unavoidable."

In 1967 Clark and the Lotus 49 won four grands prix, twice as many as any other driver, but the team's reliability was no match for Brabham's, and Denny Hulme took the world championship. While Brabham continued with Repco engines in '68, Hulme joined Bruce McLaren, whose team would be running the DFV.

Chapman was less than thrilled when the engine became available to teams other than Lotus, but that was the deal that had been struck. And if, following the death of Clark early in 1968, Hill went on to take the title in a Lotus, his major opposition came from a team new to Formula 1.

The previous year Ken Tyrrell, running an F2 team, had been entertaining thoughts of moving up, and that first victory for the DFV at Zandvoort made up his mind.

"I flew over for the day to watch," he remembered, "and it was clear that the DFV was the only engine in the race. Everything else was just old-fashioned rubbish. If you wanted to do Formula 1 in the future, this was the engine you had to have. The DFV made it viable not only for me, but also for Bruce, Frank [Williams], and so many others.

"You went up to Northampton, you gave them £7500, and you came away with an engine that could win you grands prix. All you had to do was put it into a reasonably competitive car, with a good driver, and you could win the next race. Almost impossible to believe now, but that's how it was.

"The timing for me was perfect. I'd been running Matras in Formula 2, and they were keen to make an F1 car, Ford had the engine - and Jackie wanted to drive for us. He came to see me, and he said, 'You can't afford me'. I asked how much he wanted, and he said, '£20,000'. I didn't have 20,000 pence! I went to Walter Hayes, and said, 'I think I can find the money, but I need to get Jackie sewn up, so we can sort things out with Matra, and so on'. And Walter didn't hesitate - didn't have to get on the phone to Detroit - he just said yes.

"In fact, I got £80,000 from Dunlop, and gave Jackie the 20 - which left me £60,000 to run the team - so I never needed the money from Walter, and I only found out later that he gave it to Jackie!"

I remember asking Tyrrell if, through all those years of using the engine, there was a single 'DFV moment' that more than any other stuck in his mind. He didn't hesitate. "Yes, the Nurburgring in 1968, where the conditions were appalling. It's true that we were with Dunlop, who made the best wet tyres, but I'll never forget the end of the first lap - the sound of a single DFV, and we didn't know who it was. Jackie came by in a cloud of spray - and then there was silence!" Already eight seconds ahead, Stewart ultimately won the German Grand Prix by four minutes.

"Before I went to drive for Ken," he said, "I'd been with BRM, and using their H16 engine. Of course, with 16 cylinders, it was as smooth as silk - but silk is bloody slow! It was heavy, and there was no snap to it.

"By contrast the DFV had its rough edges - there was quite a lot of vibration, which you'd expect with an eight-cylinder - but it was a revelation, particularly in terms of torque. As soon as you stepped on it you knew you had performance. In its first year Jimmy and Graham found it 'peaky', but obviously Cosworth sorted that - by the time it came my way it was fine."

In the autumn of 1968 another driver experienced a DFV for the first time: if for Chapman no driver could ever take the place of Clark, in Mario Andretti he saw a potential Lotus number one. After practising at Monza, Andretti was barred from the Italian Grand Prix (having raced in America the day before!), but then started his first Formula 1 race at Watkins Glen - and from pole.

"I can't say the power of the DFV startled me," Andretti said, "because we already had turbocharged engines in Indycars, and they had a lot of horsepower, but what I loved about the DFV was that, in the Lotus 49, the whole package was so driveable. I always loved the 49 and the engine was a perfect match for it.

"This was my first time in a Formula 1 car, and it was much lighter than I was used to, so the power-to-weight ratio was impressive, and the power seemed quite plentiful. My introduction to Formula 1 was stellar, because I had the good fortune to drive one of the very best cars of the moment."

At that time Andretti's focus was firmly on Indycars, and for several years he competed only in the Formula 1 races that didn't clash. "In 1970 Andy Granatelli put together a programme for me with a March 701, which was not a great car, but you couldn't fault the engine, which was a Cosworth.

"Then, in 1971 and '72, I drove occasionally for Ferrari, who had their flat-12, and of course its characteristics were very different from a DFV. Obviously it had much smoother power delivery, but when you went to an 'eight', with the DFV, you had way more torque, so at lower revs it had much more punch.

"It was all about getting used to the power delivery, and compensating for it in the way you drove. In that respect there was a huge difference between a DFV and a '12' - it was an entirely different rev range, and if you didn't use a DFV properly, it could have an upsetting effect on a car's behaviour.

"I know it's stating the obvious, but to go quick in a racing car, the whole objective is to be able to apply throttle as early as possible coming off the corner. Using a 12-cylinder engine, you'd get a third of the way through, and then you could flat-foot it to the exit; with a DFV, though, you could not do that - if you did you got too much torque when you didn't need it. You had to adjust to it, that's all."

Stewart was always a huge admirer of Matra - to this day the MS80 with which he won the title in 1969 remains his favourite car - and both he and Tyrrell were keen to continue with the marque. If they were to have a chassis for '70, though, Matra was insistent that it should be powered by its own V12, and Stewart agreed to test it.

"This was at Albi, the day after the Formula 2 race - and at 5.30 in the morning, so nobody would know! The engine was nice in many ways - beautifully smooth, and it made a lovely noise - but it didn't have any horsepower! Matra were desperately keen that we should use it, but Ken and I were adamant that we wanted to stay with Cosworth - even though it meant that, without Matra, we didn't have a car for the 1970 season. That's how crucial we thought the DFV was, and why we finished up with the March 701 - a poor car, which of course in turn led to Ken becoming a constructor in his own right."

As Stewart says, the DFV utterly changed the world of Formula 1: "Apart from being affordable, and available to anyone, what it meant was that for a number of years nearly all of us had the same horsepower, and no one had a huge advantage, so in that respect it couldn't have been more different from today. And what you have to remember, too, is the absolute integrity of Keith and Mike, in terms of producing engines of equal horsepower. I don't remember any difference between one and another. The DFV brought Formula 1 to a new level - a level it had never reached previously, and I don't think it has ever reached since."

World champion for the third time, Stewart retired after the 1973 season, having won 27 of his 99 grands prix, all but two of his victories coming with the DFV.

At that point Andretti was still three years away from committing to F1, but in 1976 he finally made the decision. The following year, in the ground-breaking Lotus 78, he missed the championship but won more races than anyone else, and in 1978 achieved his life's ambition with the beautiful 'ground effects' 79.

"When I went back to Lotus full-time, they started experimenting with a variety of things that I wish they hadn't, trying to get 15 or 20 more horsepower. In one way I loved that - you always want more power - but at the same time we lost on reliability, especially in 1977, and part of me wished they'd put the 'experimental' engines in Gunnar Nilsson's car, rather than mine!

"Of course another part of me wanted to have the most horsepower - and sometimes I suffered for it. In Canada, for example, they diminished the amount of piston rings, to reduce the friction, but the engine was using an extreme amount of oil, and with three laps to go - when I was leading by a lap! - I blew up.

"I should have won the championship easily that year but looking back I have no regrets: I always wanted to have the best, and the most, that I could possibly have, and if sometimes I suffered for it, so be it. I remember the DFV with huge affection, as well as admiration - it made careers, that engine, made so many champions.

"Everything about it, the size, the compactness, the packaging... for a race car designer, it was a dream engine - and, Jesus, it was so versatile! They took it to Le Mans, and it won; they turbocharged it into the DFX, and it won Indy. After my last race, at Laguna Seca in 1994, Cosworth rebuilt my engine, and then sent it to me for Christmas - as a table! I have it in my sports bar at home to this day.

"I remember the DFV with great affection - it was such a generous engine, in that it gave you everything you asked of it. Wouldn't it be wonderful if today you could go to Mercedes, get the very best engine from them, and put it in your own chassis? With the DFV, you knew that if you got everything else right, you'd win races."

If Hill was the first driver to win the world championship with a DFV, many others - Stewart, Jochen Rindt, Emerson Fittipaldi, James Hunt, Andretti, Alan Jones, Nelson Piquet, Keke Rosberg - followed. For 17 consecutive seasons it won grands prix, with a final tally of 155. The greatest racing engine of all time? Stewart and Andretti have no doubts.