British Grand Prix: Upgrade down to drivers - McLaren .

McLaren will let drivers Jenson Button and Lewis Hamilton decide whether they should run their latest upgrade for the British Grand Prix at Silverstone.

The British team have developed a blown rear diffuser pioneered by Red Bull and are expecting significant improvements.
"We would like to take it this weekend and, if the drivers think it's good enough, it will stay on," said McLaren managing director Jonathan Neale.
"If not, then we will continue to develop the upgrade."
Mercedes, Renault and Ferrari all introduced their own interpretations of the aerodynamic upgrade, which improves airflow to the car's diffuser and improves downforce, at the European Grand Prix last week.
Ferrari in particular were pleased with the results of their latest amendment to the F10, although their gains were tempered by Fernando Alonso's problems with the safety car in Valencia, which meant the Spaniard finish in eighth place.

I'm confident that we've made a reasonable performance step McLaren managing director Jonathan Neale

Red Bull have run the blown rear diffuser since the start of the season, and their car is clearly the fastest in F1, with other problems leaving them in second in the constructors' championship this season, 30 points behind leaders McLaren.
However, Red Bull team principal Christian Horner said his rivals have placed too much emphasis on the diffuser and its benefits, an opinion shared by Neale.
"In Formula 1 it's rare there are golden bolts that will transform your car from uncompetitive to competitive," said Neale.
"Most teams, including Red Bull, made an impressive change to their diffusers to give them a good step forward.
"It's one of the things we are working on as part of a package of changes that we are bringing to the next race and subsequent races.
"A lot of teams upgraded their cars quite heavily last weekend, we've been trying to pull forward a variety of packages we have planned through the season.
"Friday will be a testing day. A number of teams are working with complex projects like blown diffusers and f-duct systems, there are a lot of installation issues which require track time to get right.
"I'm confident that we've made a reasonable performance step. Do I think we've got everything we've expected? It's hard to tell at this stage, I'll wait and see what the drivers think."
And Neale hinted at further improvements to come with upgrades of "reasonable size" for the German Grand Prix on 25 July, along with the Japanese Grand Prix in Suzuka on 10 October.
"All upgrades are in the concept stages," he added.
McLaren drivers Button and Hamilton arrive at Silverstone with two race victories apiece this season and with only six points separating them at the top of the drivers' standings.
Red Bull duo Sebastian Vettel and Mark Webber lie third and fourth in the championship.