2008 German GP Technical Review

Hockenheim ended the mid-season run of conventional tracks, as the next run of races alternates between tight, or street circuits and much faster tracks, before the end of season flyaway races.

This made Germany a critical race, especially as it was preceded by a test that was attended by all the teams. Most have now slowed down the development of parts for their 2008 cars, aside from preparing their one-off Monza package.

Now alternating with the Nurburgring track as the venue for the German GP, Hockenheim hadn't run a race with the current Bridgestone tyre. Thus the test was an important one for to set up the cars and to try new parts before the August testing ban.

In its current guide, the track is not the super-fast layout of the 80s and 90s. The new inner loop keeps the cars nearer the grandstands and at a slower speed. The set-up therefore tends to be higher in downforce and closer in character to Magny-Cours than to Monza. Brakes and mid-range engine response are more critical than aero efficiency or power.

However, with the weather at Hockenheim not quite as bad as it was in Britain, the last litmus test was somewhat dulled. Unusually for this race, the weather was cool and the sessions interspersed with rain.

The lower track temperature conspired with the lack of fast corners and some teams struggled to get their tyres working as well as they had at the previous week's test. The track favoured the teams who are harder on their tyres, particularly with the harder of the compounds. Yet some of these teams still found the softer tyre not lasting as long as they'd hoped.

This issue of tyre usage shaped the battle between McLaren and Ferrari, explaining their relative pace and pit strategy in the race. However, the practice sessions clearly showed McLaren have now developed their car to be a match for Ferrari's outright pace.

Ferrari

Ferrari's development has been far more subtle mid-season than McLaren's. This is typified by the two small visible changes to the F2008 this weekend, one being the joining of the pod wing and bargeboard, and secondly the windshield.

Even Ferrari's take on the pod wing bargeboard vane is quite simple. Merely a thin strut joining the two parts, where as other teams have created a much larger surface area to direct flow back around the sidepods.

BMW Sauber have now copied the popular cockpit fins © Scarborough (Click to enlarge)

Ferrari have erred from common practice with a new wind shield set up, no longer using a simple clear plastic screen bolted to the cockpit surround and instead introducing a painted carbon fibre trim. This creates a slightly more streamlined shape than the vertical face of the clear version raced to date. It's doubtful that the screen has a significant effect on aero performance, the change is most likely to be for driver comfort.

BMW Sauber

More convergence in design came from BMW Sauber, who adopted cockpit fins for Hockenheim. These realign the flow rising up over the front suspension from the front wing and actually create lift in order to flatten the flow back over the sidepods. Despite this loss, the improved flow to the rear wing increases the car's total downforce.

The fins also create a tip vortex that adds energy to the flow passing under the sidepods' undercut.

Honda

Having successfully tested these parts before the race weekend, Honda featured new bodywork around the middle of the car. This comprised new bargeboards, a pod wing vane, and cockpit fins.

The Honda's sported all new bodywork ahead of the sidepods © XPB (Click to enlarge)

The parts are a clear progression of Honda's existing aero philosophy, with add-ons inspired by those used by most other teams.

In following this approach, the new bargeboards retain the stepped trailing upper edge, but the serration's are now sloped rather than near horizontal. At the board's trailing edge, the small flip-up is moulded into a shapely pod vane to connect to the pod wing. Above this pair, the monocoque gains a pair of fins mounted near the cockpit opening.

Although the bargeboards have a major impact on underfloor airflow, these changes appear to be aimed more at top body flow. Each of the changes would alter the flow around the lower part of the sidepod flanks and improve downforce by creating a faster airflow over the top of the diffuser.

This airflow works with the gurney flaps above the diffuser to pull more air through the floor, making it more efficient for its limited size.

More focus will be placed on the FW30 aerodynamics, starting with a new addition to the flip ups © Scarborough (Click to enlarge)

Williams

From their early season position of success, Williams have been caught on pace by their rivals. What's more, they have admitted the car suffers from aero sensitivity, meaning they have enough downforce, but that downforce isn't always available depending on the attitude of the car on the track. They have made steps to draw resources from their 2009 car to improve the performance of the current car.

One small sign of development was a change to the sidepod flip-ups. These gained a Ferrari-like flick under the main flip-up. It's doubtful this was the only development on the car for Germany and that it is a major step towards the sensitivity issues which are more likely to revolve around the more aerodynamically influential front end of the car.

New mirrors and pod wings were raced, while the wheel fairings only appeared on Friday © Scarborough (Click to enlarge)

Force India

Following their major upgrade at Silverstone, at Hockenheim Force India brought yet more revised parts for the VJM-01. These featured in two areas, new pod wings and wheel fairings, although only the former was raced.

Having altered the sidepods for Silverstone to vent more through louvers than the chimneys, the team also merged the pod wing into the sidepod in a different way. This part was further changed for Germany with the trailing edge of the pod wing no longer merged with the sidepod, but now forming a part of the rear view mirror.

Force India already had aerodynamically elegant mirror supports, but these have been extended to arch down to join with the pods wings slot. Acting both as a horizontal turning vane and as a support to the pod wing, this is neat integration of the part involved. Its design harks back to the first iteration of pod wings, which when they appeared on the Jordan spanned across the width of the sidepod.