Jean-Pierre Fleur (Pipo Moteurs) The Lions' Heart-- As Peugeot Sport's official engine tuner, Jean-Pierre Fleur -- otherwise known as 'Pipo' -- is the man in charge of the 307 WRC's power-plants. We talked with him prior to the demanding ...
The Lions' Heart--
As Peugeot Sport's official engine tuner, Jean-Pierre Fleur -- otherwise known as 'Pipo' -- is the man in charge of the 307 WRC's power-plants. We talked with him prior to the demanding challenge of the Cypriot inferno--
Q: What are the main features of a World Rally Car engine?
JPF: "It's essentially a two-litre, turbocharged engine, although the FIA regulations dictate that the turbo comes with a 34 mm air restrictor. The main difficulty is the fact that we work on what is a production engine, a normally-aspirated unit onto which a turbo has been grafted for competition use. Compared to the standard engine's relatively low torque (20 mkg), we obtain three times that value with the turbocharged rally version. Thankfully, Peugeot's engines are modern in terms of their design and construction. Those that power the 206 WRC and the 307 WRC lend themselves perfectly to this sort of extreme use."
Q: Is the 307 WRC's engine very different to the unit that powered its predecessor?
JPF: "They both come from the same familly. The XU7 engine, which replaces the XU9, is practically identical as far as the block is concerned. However, its cylinder head is more modern and this, along with a number of other parts, has enabled us to achieve a significant gain in efficiency."
Q: It is said that the turbo restrictor complicates the quest for extra power--
JPF: "The restrictor was a deliberate choice by the governing body and it effectively does its job; less air is a natural way to keep power outputs down. As a consquence, we make a special point of making the most of the little scope for work we have by optimising combustion and mechanical efficiency. Since we can't go hunting for extra horsepower, we aim to obtain the highest rev range possible."
Q: Does the existence of an air restrictor not entail a risk of engine development stagnating?
JPF: "I don't think so. It's a rule that equals things out for everyone and that limits the areas in which engine tuners can work. But it doesn't prevent them from working. Every tiny improvement counts and development is going on all the time. From the first campaigns with the 206 WRC to the potential of the engine that currently powers the new 307 WRC, we have made significant progress, in all domains, beginning with the engine's integration in the chassis and mechanical accessibility, a primordial consideration in rallying. And our rivals work too, which is why you can never stop. From the engine's weight to its fuel consumptiion and driveability, no parameter is neglected. We explore a number of avenues, some of which turn out to be workable and we have two dynos dedicated exclusively to development--"
Q: What has been the most significant evolution in recent years?
JPF: "The way the team works together. Work methods have evolved at the same time as the car. A modern World Rally Car has to be considered in its entirety and no longer as a collection of assemblies that are simply bolted together. Optimisation of engine performance is conditioned by all the peripheral elements associated with it, and I am tempted to say that that now extends right down to the tyres which are in contact with the ground. Engineers, engine specialists and electronics experts today function as a group, right from the design stage. The widespread use of electronics and the simulation tools at our disposal add to the necessity for interaction between everybody's respective expertise."
Q: Rally Cyprus is reputed as being particularly tough on engines. Why is this?
JPF: "In addition to the heat, the very slow and twisty stages make enormous demands on engines. The lack of fast straights that generate cooling air means they run for long periods at a time at very high temperatures. We therefore aim to optimise cooling, and even to curb power output in case of overheating. In itself, this isn't a major handicap since the engine is rarely used at full song on this type of rally."