Features - Interview
MARCH 1, 1990
BY JOE SAWARD
As this was happening a new generation of French engineers was also cutting its teeth with Matra at Villacoublay-Velizy, Gordini (Renault's competitions offshoot) at Viry-Chatillon, and Alpine at Dieppe.
These were heady days for the young Frenchmen, success followed success and ultimately the French, with substantial backing from companies such as Elf, looked to Formula 1 racing.
By 1971 he had been responsible for the A360 F3 engine, a light alloy 1600cc unit based Renault 16TS engine. He was also beginning to toy with the concept of turbocharging.
In 1972 Dudot produced a one-off turbocharged 1600cc rally engine which won the Criterium des Cevennes that year.
At the same time at Gordini Francois Castaing was at work on a 2.0-litre normally-aspirated engine which would ultimately grow to dominate the Formula 2 scene.
It was not long before Gordini began to look at Formula 1 racing and winning the Le Mans 24 Hours. And they began to look at the possibilities of turbocharging and people with experience in the field.
The idea of turbocharging the modern racing engines is credited to Jean Terramorsi, the then Director of Gordini. In 1973 he recruited Dudot from Alpine and sent him off to California to research into turbocharging.
Dudot returned to France convinced that turbocharging was the way to go in the future.
As Renault moved into Formula 2, Dudot was named to head a parallel project, Alpine cars powered by Renault-Gordini engines. These would dominate the European two-litre sportscar championship in 1974.
Very quickly Dudot and Jean-Pierre Boudy (who would ultimately go to Peugeut to work on the 205 T16) began work on a turbocharged version of the Castaing's original V6.
By then things were moving fast. In April 1975 the Renault board made the decision to go to Formula 1. Within a matter of months, the first turbocharged EF1 engine, designed by Castaing ran on the test bench. At the end of the year it had been track tested.
At the same time there was considerable consolidation going on, Renault took over Alpine at the start of 1976 and Renault Sport was created in the Gordini works at Viry Chatillon under the management Max Mangenot.
The early days of both the F1 and the Le Mans project were not easy. It took until 1978 before Didier Pironi and Jean-Pierre Jaussaud finally won Le Mans in the A442. Thereafter Renault closed down its sportscar operation to concentrate on its Formula 1 operation.
Dudot was appointed Head of the F1 engine porgramme under Technical Director Castaing.
Although the project (and the later customer programmes) would result in 15 Grand Prix victories and 31 pole positions, the Renault engine never managed to power a driver to the Drivers' World Championship.
By 1980 Castaing had quit and Dudot took over. Boudy too left to go to Peugeot to be replaced by Jean-Jacques His.
Finally at the end of 1986 with a new Chairman and increasing criticism at the lack of success, Renault suspended its Formula 1 programme. His left to join Ferrari and Dudot's department turned its attention to other, road-car related, projects.
At the same time, the company deliberately left open the possibility of returning with a new normally-aspirated F1 engine. This year they will do just that, a new V10 engine, designed by Dudot and his team of 20 engineers at Viry, powering the Williams cars of Riccardo Patrese and Thierry Boutsen.
Dudot was at the 20eme Salon de la Voiture de Course in Paris last week giving details of the new project.
Now 50, Dudot has the air of a man who has experienced just about everything that motor racing can throw at you. He was with the company from the start of the turbocharged Formula 1 era and has seen both the rough and the smooth of Grand Prix racing. His sense of humour is finely tuned.
His English is idiosyncratic, but good to listen to. Like Peter Sellers' Inspector Clouseau, he has trouble with some English pronunciation and the words are not always in the right order, but you can understand exactly what he means.
"When we stopped the turbocharged programme at the end of '86," he says. "three or four months later we had an agreement from the President of Renault for 15 people to start work on drawing the new engine.
"We made some drawings of V8s, V10s and V12s with different angles and we took them to chassis engineers, people like Gerard Ducarouge and some engineers from Gerard Larrousse, and we asked them 'What would be your choice?' Generally they chose the V10, according to the range of power we indicated.
"At the end of '87 we had built four engines, a small pool of engines to start the tests. The first ran on the test bed at the end of January 1988. Really I was very surprised that we had not very large problems. There were a few small ones, like oil leaks, but the engine started immediately and it did a lot of tests with no big blow-ups. It was completely different with the turbocharger. The problem we had then was that we did not have the experience and also the suppliers had the experience. It was a problem for us with pistons, valves etc.
"In the middle of October 1988 we tested two engines at Paul Ricard with Riccardo Patrese driving. We have now done about 4000km testing and we are sure that before Rio we shall make about 5000km minimum."
Until this year V10 engines had been shunned because of the belief that they were unbalanced. Has this caused any problems?
"Absolutely no problem," says Dudot. "We knew when we started the drawing about possible problems and we examined a lot of solutions about crankshafts angles and weight. You have two types of movements on a V10, sideways and up and down, the consequence of these movements are vibation in the chassis which can destroy the fixing points and cause problems with exhausts and alternators, things like that. It was important to have good knowledge of this problem and we worked a lot on that.
"The engine is very smooth compared to the V8 for sure. The V12 is normally is not bad with vibration, it has a good balance."
The V10 is essentially a compromise between power output, size and weight. Would a V12 have been a better solution if there had been no problems with installation?
"Probably, if we had had no consideration for installation and weight. The V12 also has a small problem with the fuel consumption. Fuel consumption is very important. If we can start on the grid with three or four kilos less fuel than the Honda or Ferrari it is better. At Rio 20 kilos extra costs 0.9secs on a lap. It's a lot. If you gain five kilos, it's 0.2sec. Weight is very important. We having nothing to gain with the weight we have everything to lose.
"At the end of the turbo era, with 150 litre of fuel, the turbos were still quicker than the atmospheric engines. Temperatures were higher in the engines. That was only possible through metallurgy in the turbos. Now we don't need fuel to cool the engines, but we have not as good efficiency as the turbos. Fuel efficiency will be computer-controlled exactly like with the turbocharged engines and sometime, maybe, I believe that it is not impossible that we will run out of fuel."
The new F1 challenge is to find more power and less weight. Which will be more important?
"We have to work in both ways," he explains, "but really with the new formula 500 kgs will not be very easy to get with the new type of longer engines. It will be difficult to be at the weight limit. For that we have to make some progress with both chassis and engine to be sure to be under the weight limit at the start of the season because you always gain weight during the season.
"The range of the engine is also very important, so you can use the power. When you have an engine with a narrpw range of power, you change the balance of the car. When you accelerate the car is coming from oversteer to understeer. That loses a lot of time. If you have a very good range of power you can adjust the balance of the car quickly, chose tyres quickly and it is easier for the drivers.
For me, the better performance of the cars now, compared to the turbos of last year, is because the engines are very smooth and the cars are easier to balance. The improvement is not in power. You do not have the same power as last year when 680bhp was not unusual.
"Now everybody has less power but the range of torque and power in bigger."
So what sort of power outputs does Dudot expect this year? No comment. Minimum power?
"Three hundred horsepower!" he laughs. And what about the touchy subject of revs. How high will the Renault be revving?
"I don't remember," he says with a quiet smile. "It's a secret. But, you know, it is easy to find out how many revs everyone has."
There is consternation amongst the gathered pressmen.
"No really," he smiles, "you need a tape recorder. You record the engines on the straight and take the tape to a laboratory. They can tell you the maximum revs from the sound frequency."
Has Renault done that? "Sure we have. Everybody has. You cannot imagine the number of tape recorders you can find on the straight at tests like Jerez. One coming from Ferrari, one from Renault another from Honda and one from Ford!"
Finding out about the other manufacturers is part and parcel of F1 today. Renault knows a great deal about the new Ferrari engine -- thanks to the return to Viry of Jean-Jacques His. What do they know about Honda?
"I believe that our engine is not as high, a little narrower and the length is very close to the Honda." says Dudot with another quiet smile.
"We are start with a very conventional engine, we have small materials in some places, not a lot of ceramics and no plastic, but we are working at that and we have a special engineer in our factory for all these problems. He is working only on ceramics, plastics and carbon."
And what about the electronic systems? "Now we use a completely different system from the turbos," he says. "It is Marelli-devised but to our own specificiations. We have an electronic workshop to work on this type of development. I believe that we have a lot of experience about electronic management. It is done completely at Renault Sport, but we are using knowledge of Renault for calculation and laboratory work.
The search for less weight, more power and fuel efficency and the right range is sure to push up F1 prices in terms of research. Will Grand Prix racing be more expensive even than the turbo days?
"I believe that we shall start with the price lower," says Dudot. "We shall increase very quickly according to the development on the speeds of the engine. Now we are at a low price, less expensive than the turbocharged cars of 1986, but it will go up a lot."
Have there been many changes to the Renault engine thus far? "No, not really," he says. "We have done normal work when you start adapting to a chassis, modifiying small things to make sure we have a perfect integration with the engine and the car. Immediately after we signed the contract with Williams in June we had meetings with Patrick Head. I am very happy with the collaboration with Williams. It is very good. Patrick is a very scientific man, very precise. It's very important. We speak two or three times a week and there is a fax every day."
Honda ha already altered its engine, changing its belts and pulleys to gear drive. Is Renault planning something similar.
"This engine," says Dudot pointing to a V10 in a display cabinet beside him, "is very simple. There is nothing to change. There is not enough advantage to use gears in the race in terms of weight.
"We are going to use pneumatic valves, that won't change. The engine speeds will be so high that the pneumatic valves will be an advantage because we can adjust the pressure accoring to the air. It is not an automatic system, not yet! But, why not! In the future, with new materials, it may become possible. "You have nothing to gain with weight," he says. "And everything to lose."
You sense that Dudot is delighted with his new challenge. Renault is back and looking forward to the fight with Honda and Ferrari. In Paris, they reckon, although Honda is ahead now, nothing is impossible. They are looking ahead to another French renaissance in motor racing. And the man who was there at the start, intends to be there at the finish...