JULY 13, 2010

The secret of Red Bull's qualifying speed

It looks like Christian Horner was right when he said that there is a lot more to Red Bull's pace than simply a blown diffuser. And, even successfully getting the best out of a blown diffuser is no easy task, as Mercedes and McLaren proved in Valencia and Silverstone respectively.

From the very start of the season, Red Bull's qualifying pace has been much stronger relative to the opposition than its race pace and so it was again at Silverstone. Sebastian Vettel's pole position time was 0.8s quicker than the McLaren pace but in the race, although Mark Webber was doubtless controlling the pace, Lewis Hamilton was comparatively close.

It's a pattern that has been seen regularly in 2010, and one exaggerated at circuits with high speed corners, which plays to Red Bull's strengths. At Barcelona, for example, the RB6 was something like 9mph quicker than anything else through Turn 9, and enjoyed a similar margin at Silverstone's new high-speed right-hander at Turn 11.

At first, the paddock suspected that Red Bull had a method of controlling the ride height, so that the car could run lower, which is advantageous, in qualifying but then compensate when fuel was added for the race, bearing in mind that the F1 regulations forbid you to make changes to the car between qualifying and race.

The blown diffuser concept is not new but adopting the principles around the existing car dimensions is what has been the challenge.

As long as the driver is on the throttle, the exhaust is putting additional energy through the diffuser and hence increasing downforce. But, when he comes off the power, that energy stops, and hence you get varying degrees of downforce which can lead to a tricky, unbalanced car. Both McLaren drivers had issues with that at Silverstone, Button labelling the car undriveable at one point.

Williams technical director Sam Michael, meanwhile, was interesting on the subject of his team debuting their blown diffuser at Silverstone, with strong results.

"All the systems are different," Michael said. "Ours is most like the Red Bull when you look at the exhaust exits and how we are working the diffuser, but the Mercedes one, Ferrari and to an extent McLaren, which I haven't seen properly as it was only on for a day, are different.

"They all vary by where they blow the diffuser. You only have a certain amount of energy so you can't try and blow all of it because there's not enough puff, you might say. There's only a certain amount of energy in the exhaust and you have to choose where you blow it. Red Bull's is obviously fully optimised and it made sense to have a look at what they were doing."

Michael would not elaborate but, with a wry smile, said that it was quite useful when Mark Webber took off over the back of Heikki Kovalainen in Valencia and gave everyone a good look at the bottom of the car!

Michael is also convinced that Red Bull is using some sort of throttle trail system to produce more stable and consistent downforce from a double diffuser which already has a bigger area due to Red Bull's lone adoption of pull-rod rear suspension.

"It's very easy from a chassis point of view," he explains, "but the problem is doing it without damaging the engine, because you've got to retard the ignition significantly so that you get the gas to fire in the exhaust system and produce a lot of high energy air coming out of the exhaust but for very low engine torque. Doing it places considerable strain on the exhaust vales.

"We're into that but we haven't done it at Silverstone. We're trying it with Cosworth on the dyno but haven't got anything signed off for now. Judging by their pace you'd probably say that Red Bull are the only ones doing it at the moment, although Renault is using the same engine so they've probably got something signed off too.

"It also increases the fuel consumption and so it's not something you would do in the race, only in qualifying. It's only for one or two seconds when you hit the brakes, so it's not like running a retarded mixture all the time, so it's pretty realistic to get it done, we just haven't done the work yet."

Could it be that some frantic work in that direction might close up the grids as the second half of the year develops?