Mercedes had arrived at their home race in Hockenheim with a modification to their exhaust blown diffuser and a new rear wing.

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Red Bull are running with a new 'double' diffuser in the Principality while championship leaders Brawn also have a series of modifications, including a new rear wing configuration, changes to the car's suspension and a reconfigured chassis to suit the tight, twisty track.

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Championship leaders Brawn arrived in Budapest with a major upgrade package which includes a new diffuser, rear wing and bodywork and they used Friday's first session to test their new parts with race fuel loads.

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Other upgrades include a new spring-loaded, adaptive rear wing and the Triplex rear suspension, comprising a bidirectional hydraulic strut mounted horizontally between the pushrod rockers.

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New rules have forced modifications which lower and widen the front wing, and demand a tall, narrow rear wing.

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New 2009 regulations have forced modifications which lower and widen the front wing, with a tall, narrow rear wing.

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