Honda has upgraded its internal combustion engine (ICE) in time for McLaren's home Grand Prix.
The move follows the upgrade introduced for Canada, which saw new turbochargers fitted along with a new fuel from ExxonMobil which was expected to increase horsepower.
The upgrade to the turbocharger was not so much about increasing the grunt of the Honda unit, rather improving the efficiency of the harvesting of the power unit which in turn was expected to improve lap times.
However, it is understood that though the update did improve efficiency it was at the cost of power.
The Silverstone update, which necessitated the use of two of the infamous development tokens, is understood to relate to the intake system on the ICE and aimed at improving the combustion efficiency and power output.
The update does not require a new unit but Fernando Alonso will take a new one - his fourth of the season - for strategic purposes. Teammate Jenson Button, who finished a strong sixth in Austria last weekend, will stick with the same unit but have the update fitted.
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