2008 French GP Technical Review

Running to a slightly different schedule this year, the French GP marks the mid-point on the season. Coming off the back of the Canadian GP, Magny-Cours kicks off the mid-season run of European races. Thus, the teams return to a more conventional circuit, although the track has its idiosyncrasies.

Placed in the centre of France, the Nevers track is mix of tight hairpins and rapid changes of direction, plus a single challenging right-hand turn. To attack these bends and without a long straight to offset the aero map, the teams need a high level of downforce.

While its layout it quite normal, the track's surface is very much a one-off on the calendar. It is completely smooth and bump-free, allowing the cars to run low and stiff set-ups, although the kerbs at the chicane ending the lap require some suppleness in high-speed suspension response.

Additionally, the dark tarmac changes temperature with sunlight, and the track's location in the middle of agricultural land means that it is unshaded. As the track gets hotter its grip level lessens, making set-up and timing of qualifying runs particularly difficult.

Without a long straight, the flowing nature of the sectors tend to leave the car in a gear for longer periods. In fact, Magny-Cours has the second-least number of shifts per lap of any circuit.

As the car is shifting less, the track demands a very tractable engine as the throttle is part open for such a large percentage of the lap.

In contrast, the throttle is wide open for a very small part of the lap, negating any peak power advantage. This reflects on the relative pace of some cars during the race weekend.

The several hard braking zones and generally high temperatures make cooling an issue for engine and brakes alike. Many teams ran with quite open sidepod arrangements and larger brake ducts. The cost in drag for this extra cooling is an easier trade-off at this track due to the lack of a long straight.

One quirk is that the lap requires different level of brake bias, there being some heavy straight-line braking zones into the hairpins as well as more balanced decelerations into the faster chicanes.

Without the electronic braking aids this makes life harder for the drivers, and many teams have a quickly adjustable braking bias lever akin to Ferrari's quickshift system to change from one bias setting to another in between corners.

As the first race of second half of the season, France signalled many detail updates to the cars. In the remaining races there are six conventional tracks (Silverstone, Germany, Spa, China, Japan and Brazil), with three slow/street circuits (Hungary/Valencia/Singapore), plus the one-off high-speed event at Monza.

Between now and the end of the year the emphasis for development will be to get the cars aero efficiency set up for the classic tracks. Thus, recent testing has largely focused on general aero and suspension improvements.

With the calendar panning out the way it is, Silverstone will probably be the last track for major steps by most teams, who will hope these developments last the car through to the end of the year.

But with the championship so close, some teams will need to continue to develop their 2008 cars, which is surely bound to impact on their preparations for the very different aero and tyres rules for 2009.

Ferrari

Running with their larger Monaco front wing and nose hole, Ferrari did not appear to have any visual updates. In the race Kimi Raikkonen's car suffered an exhaust failure. It appears that the secondary pipe that that joins the collector broke off, only remaining attached by the wire that connects the lambda sensor.

From the flapping of the errant pipe on its wire and also from the heat, the engine cover of the car sustained significant damage. Heat from the exhaust had burnt through the bodywork, all the way into the airbox. At the race's end, the inlet trumpets and fuel rail could clearly been seen through the hole.

With the airbox no longer pressure-sealed and part of the exhaust missing, Raikkonen would have suffered a drop in engine performance. Certainly for several laps he took a while to find an engine setting that reduced the exhaust's temperature and still gave him a usable power range.

The danger with broken exhausts, aside for the obvious danger of a length of Inconel flying off into the scenery, is that the exhaust gases are no longer routed where they should and can overheat carbon fibre parts and wiring further back down the car.

This usually effects the rear suspension and beam wing. Teams have sensors laid into these parts to measure their temperature and the telemetry that passed from the car to the garage during the race would have informed the team about how critical the temperatures were on the rear of the car.

It was for this reason that Raikkonen would have tried to run the engine on a setting that reduced exhaust gas temperatures.

Renault

Renault produced a range of small updates to the car for its home race in France, covering the front wing, diffuser and some suspension changes.

The front wing gained new flaps. Up until now, despite the aggressive front wing having a square-jawed middle section on the main plane, the flaps then curved to form more conventional shape.

The new flaps now follow the same square format as the leading element of the wing. This change puts more wing area in closer proximity to the ground, which improves the ground effect produced but can make the wing more sensitive to attitude changes. Clearly Renault has been able to make the new flaps as insensitive as the front section, creating more downforce for no loss in sensitivity and drag.

At the rear of the car, the brakes have been modified. These parts have little to do with brake cooling and are aids to the airflow out of the diffuser.

Just as with Williams and Ferrari, Renault has added small vertical vanes to the brake ducts - these create an extension to the sides of the diffuser, creating more downforce without adding extra drag.

Combined, these development will aid Renault's aerodynamic efficiency, most likely to aid top speed. The rear wing needs to contribute less to create the downforce required, and hence creates less drag to slow the car on the straights.

Williams Toyota

Following this season's fashion for conjoined pod wings/bargeboards, Williams brought its take on the design to France. Sam Michael told Autosport.com: "We call this a SIS (side impact structure) sail".

Williams's is a more shapely solution than most other teams. The space created by undercut sidepod and protruding pod wing allows the team to add a vane to aid flow around the sidepod.

Williams's version is slim at its mounting points but widens to create a larger surface area. This new part requires longer pod wings, and Michael added that the parts were for "just a small downforce gain overall."

Along with the SIS sails, Williams produced updates to the suspension. Again, Michael was able to expand on the purpose of the changes:

"The mechanical side of our development program has a target of improving slow speed grip. It includes items related to suspension geometry, steering and brakes".

Additionally, the much talked about subject of inerters or 'J-Dampers' has prompted reports that Williams first raced these devices back at this year's Monaco GP. This would have put Williams behind both Ferrari and Red Bull on their development. But Michael was able to correct these reports:

"We've been using inertia devices within the suspension for a couple of seasons now," he said. "These devices are continuously refined and developed. We have had some recent updates to these parts."

Their early adoption of this technology predates most teams, although McLaren was still the first to bring these devices to F1. Their long served presence on the Williams probably explains the car's extraordinary grip, as witnessed at the past three Monaco GPs and other low-speed tracks.

Toyota

A deserved podium place for Jarno Trulli in France paid respect to Ove Andersson and also to the detail development being made to the car through this season. In both testing and at the French GP a few new developments had been noticed.

Firstly, on the last day of Barcelona testing before the GP, Toyota debuted new front wheel fairings. Last year Toyota was one of the first teams to adopt the static fairings on the front, and this year a finned fairing has been raced attached to the rear wheel.

The new front wheel fairing copies the rear versions, with a heavily vaned cover bolted to the wheel. The vanes will aid airflow through the wheel to aid brake cooling, but would appear not to aid the flow around the car.

Pascal Vasselon told Autosport.com: "We were the second team immediately after Ferrari to successfully race a static front rim blanking in 2007, so we are quite experienced with these devices and with the benefits that can be gained from a static rim blanking.

"The rotating rim blanking is potentially, for our flow structure, a better compromise between front corner cooling requirements and management of the wake of the front wheel assembly. There is no regulatory issue with either the static or moving solutions."

Other teams have as much as four percent increase in downforce from these covers. Although the finned fairing would appear to be on the edge of the spirit of the rules, the same could be said of the static fairings, so no protest is likely to be lodged.

Also at the front of the car a new front wing was raced. The wing follows the same basic shape as the old wing, only the outer tips are raised up slightly. The bigger difference is in the endplate. The upper edge of the endplate no longer has a notch and now sports a small fin on its trailing edge.

Along the lower edge of the endplate, the footplate now starts flat and bulges to form a venturi. These changes are probably not aimed at improving peak downforce, but improving the wing's performance when the wheels are steered.

One point to note are the three large pockets set into the front wing main plane. These are to house ballast and have appeared over the past few races. This will allow Toyota to push yet more weight forwards despite the car's redesign over the winter, part of which was aimed at the same goal.

It's clear teams are finding that the Bridgestone tyres respond to ever greater amounts of load put on to the front tyres.

McLaren Mercedes

McLaren continued its detail development to the front of the car, the first stages of which were seen in Canada. For France the car gained new add-ons to the front wing, cockpit sides and sidepod inlets. This is part of McLaren's aim to produce upgrades at each race.

McLarens spokesman told autosport.com: "we do try and bring at least 0.1-0.2s' worth of improvements to each race, and these are simply the result of our development programme."

Under the front wing the usual fences to route air around the front tyre was doubled up, there now being two closely-coupled fences each side of the wing.

Around the cockpit the usual McLaren fins have been swapped for a more Ferrari-like fin, the new versions being longer and swept back. These help direct flow towards the pod wings and around the sidepods' undercut.

Just behind these was a new sidepod inlet stuffer. McLaren has altered the size of the inlet numerous times to tune cooling capacity for greater aerodynamic efficiency. A simple moulding fits inside the inlet to divert flow away from the inlet around the sidepods' undercut.

We want to hear from you!

Let us know what you would like to see from us in the future.

Take our survey

- The Autosport.com Team

Read and post comments