Engine supplier Renault insists that the FIA-mandated change to Red Bull's engine map will not cost the Milton Keynes team a great deal of time, despite both Sebastian Vettel and Mark Webber languishing down the order in free practice at the Hungarian Grand Prix.

Red Bull was referred to the stewards after qualifying for last Sunday's German Grand Prix when technical delegate Jo Bauer believed that the engine maps of RB8 allowed reduced torque level in the mid rpm range, breaching the technical regulations [read here]. Although the deliberation that then took place ahead of the race resulted in no action being taken against RBR [read here], the governing body reacted by closing what Bauer perceived to be a loophole in the wording of the regulations in the short week that preceeded the trip to Hungary, with the rewritten rule requiring all teams to 'nominate any one engine map used in the first four races of the season as a reference map'.

Asked how the change could be expected to impact on Red Bull's performance over the second half of the season, Renault Sport's R?mi Taffin, who oversees the team's relationship with its engine supplier, maintained that the difference would be measured in fractions, although Vettel and Webber ended the second Friday practice session in eighth and 14th positions overall.

"We're not talking about big changes," Taffin claimed, "We're talking about an ongoing process [where] obviously, race after race, you try to optimise your package and engine maps are part of that - that's what we've been trying to do since the beginning of the year. When you talk about engine maps, it's something that is done by everyone in the pit-lane, so that's not something unusual.

"Let's take the example of the engine map we've been talking about. It's basically what the engine is able to produce as torque during the weekend, for example here. And that's where is the bulk of the part to play with in Renault engines. It's very difficult to quantify [how much of a change in performance there will be], but... we're talking about hundredths and not at all about seconds or tenths. We all know that, [with] every bit on the car, we're going to be working [on it] to get the [last] hundredth out - that's part of the job."

Taffin confirmed that there had been no preferential treatment for Red Bull when it came to providing engine maps, but that none of Renault's other clients had opted to run with the torque map employed by the reigning champions.

"We've got an area in which to play, and each of our four teams is able to choose between these things, so they are free to play with our engine as they wish, let's say," the Frenchman explained, "That's the way they do and they did, so maybe that's why we got one team that has gone to that in Hockenheim and there could have been another one one race after."

New Williams executive director Toto Wolff confirmed that the Grove team had had the opportunity to use the same map as Red Bull, but had been prevented from doing so by the way the FW34 currently operates.

"First of all, flattening out torque curves is something that every team looks at, obviously, and the reason why we have not been taking up that solution is because we didn't make it work as Red Bull have," he noted, "We have no coanda exhaust and this is why it's not as beneficial for us as maybe for others."