McLaren boss Martin Whitmarsh said after the race that the slow second pit stop of Lewis Hamilton did not cause him to lose the race, he believes that he was going to lose it anyway.
Hamilton approached the pits on lap 37, while leading the race. At that stage Rubens Barrichello had closed up to be just 3.6 seconds behind him. He had four to five more laps of fuel in the car at the time and the general rule is that you need about one second lead for each extra lap your opponent is doing. It’s probably true that Barrichello would have jumped him but it would have been close.
So McLaren was keen to get Hamilton to eek out an extra lap on the fuel to give him more of a chance. But by the time it because clear that he could do it, he was already on his way into the pits so it was too late to change course. Hamilton explained that he took the decision to come in anyway as he reasoned that he would lose too much time driving back out onto the track.
So he pitted and McLaren were not ready for him with the tyres.
Hamilton lost at least six seconds to Barrichello at that point. Barrichello then brought forward his second stop because he was going to pass Hamilton easily anyway and there was a risk of being caught by a safety car the longer he stayed out. This is why he came in just three laps later.
Without the problem it would have been very tight, as Hamilton was 6 seconds behind Barrichello when he rejoined.
Whitmarsh said, The fact is that we didn’t have the race pace to win. So we pushed it to the absolute limit, we’re not there to get second. We monitor the fuel flow and we were trying to get the extra lap.
“In doing so it cost us a couple of seconds, had we come in without the delay it wouldn’t have made any difference to the outcome. The fact is we weren’t quick enough in race pace.”
He added: “Lewis was meant to come in on lap 37, we were trying to extend him to 38 which meant swapping the drivers over in the pit order. At the time we had Heikki racing Kimi and Lewis racing Barrichello.
“We decided at the last minute that the best hope of winning this grand prix was to allow an extension, which meant an early stop for Heikki. And that changeover… the guys were waiting for the stop but they didn’t know whether it was going to be Lewis or Heikki.”
At times like this the teams take some serous risks with running out of fuel. Had Hamilton been able to carry on and do the extra lap he would have had about a kilo of fuel left in the tank when he came into the pits. That would be cutting it fine in your road car, but in a racing car which devours 2.6 kilos of fuel per lap, it would have been very risky.