MATCHETT: A Hallowed Proving Ground

Formula 1

MATCHETT: A Hallowed Proving Ground

This weekend the F1 circus returns to Belgium's Spa-Francorchamps circuit, which, as SPEED F1 analyst Steve Matchett explains, is a classic proving ground for contemporary F1 cars.

Steve Matchett | Posted September 11, 2007 Spa-Francorchamps, Belgium

Spa-Francorchamps, the magnificent venue of the Belgian Grand Prix, is a special place. Set among the forests and rolling hills of the Ardennes, this classic (near hallowed) circuit is long, serpentine and very demanding.

Drivers often report that a lap of Spa gives a great sense of Journey, of going somewhere. I can well believe it; the track offers everything needed to thoroughly excite them and thoroughly challenge their machinery too: The circuit sweeps up and down, swings left and right; the hairpin at La Source is impossibly tight; the blast uphill from Kemmel to Les Combes is frighteningly fast. The very names of the corners are evocative, hair-raising: Blanchimont, Malmedy, Pouhon, Rivage, Stavelot�

�And, of course, there is the greatest corner in all of international motorsport, the legendary Eau Rouge: In plan-view this section of track looks little more than a left-right-left squiggle designed to annoy the cars on their run from La Source to the Kemmel straight. But Eau Rouge cannot, in any way, be appreciated by studying it on a simplistic two-dimensional track map. Eau Rouge is all about elevation change; you need to see the corner in three dimensions, to witness with your own eyes the immense elevation change from entry to exit to fully appreciate what's involved in trying to master this epic challenge.

The run into Eau Rouge is both fast and downhill, causing massive suspension compression as the car flicks left at the approach. The road then climbs, steeply, as the driver muscles the steering to the right and powers uphill. Moments later the car finds the second left-hand flick. More often than not it's this section that causes so much trouble: the track levels out, at the brow the car's suspension loads reduce, the chassis becomes instantly light and the driver finds his car's steering response and grip level have totally changed.

The elevation changes through Eau Rouge will load and unload the suspension, lower and raise the ride-height in excess of 25mm; changes that will greatly alter both the mechanical grip and the aero-grip as the floor moves so severely, altering the all-important distance relative to the track. Controlling the car in these ever changing conditions, fighting its desire to carry straight on into the waiting guardrail, is a real test of skill. As a rule of thumb (even allowing for the control Bridgestones and the horsepower reduction of the latest generation V8s) you don't have a minor shunt at Eau Rouge. This year the drivers should be able to hold the throttle wide open � they'll certainly attempt it � but a quick visit to Youtube.com will reveal several examples of what happens when things don't go according to plan at this point of the track.

Elevation changes, classic corners, technical variety...Spa has it all. (LAT photo)

Added to the natural challenges of Spa, the weather is highly changeable too. In fact, the one aspect of a grand prix weekend that can be accurately predicted is the unpredictability of the weather. A lap of Spa is well over four miles, and it's perfectly normal to find the far side of the circuit bright and sunny, while down in the pits, at La Source, the rain is pouring.

In the morning, when the teams arrive, the skies can be black, the track thick with mist. Within 20 minutes, however, the clouds have gone, the sun is shining, and any remaining rivulets are gently steaming to nothing. Within an hour of a torrential downpour the track is bone dry and Spa will try to convince the world that it hasn't seen rain for several weeks. An hour later, the clouds, the mist and the rain are back.

As to the setup of the cars, downforce requirements are midrange, this due to the two high-speed corners of Eau Rouge and Blanchimont. And while more downforce may help the cars to exit the former, the additional wing would sap engine power, killing the car's uphill blast along Kemmel, to the top of the circuit at Les Combes.

Cars running a three-spring rear suspension will have that third, high-speed spring softened a tad more than is usual for the majority of tracks, too. When aero-loading is at its maximum, this third spring is designed to prevent the car from being driven into the track at high speeds. The idea behind the concept is that the cars can be equipped with relatively soft springs at the four corners of the car, helping with low-speed cornering when downforce is minimal; these softer springs will compress as the speed (and downforce) increases, and continue to compress to a point where the third, stiffer spring takes over.

Basically, the softer springs (often referred to as roll springs) are used in the low- to mid-speed corners; while the third spring is used during the fast corners and the balls-out straight-line stuff. That said, as I touched on a little earlier, the engineers may well opt to use a marginally softer third spring at Spa, encouraging the car's handling to be a tad more forgiving while their derring-do drivers attempt to match themselves against the formidable majesty of Eau Rouge.

Spa has everything needed to test the skill and dexterity of both engineers, their cars and their drivers alike. It offers the supreme challenge. I can't wait for the weekend to be flagged underway.

SPEED's Formula 1 technical analyst Steve Matchett presently resides in the south of France. In addition to his duties on SPEED'S F1 broadcasts alongside Bob Varsha and David Hobbs, Steve will be providing insight into the high-tech world of Formula 1 through regular video features and commentary on SPEEDtv.com.

The opinions reflected herein are solely those of the above commentator and are not necessarily those of SpeedTV.com, FOX, NewsCorp, Speed Channel, or Haymarket Worldwide.

ABOUT THE AUTHOR

Steve Matchett

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