McLaren are set for another difficult weekend plagued by grid penalties as both Jenson Button and Fernando Alonso will receive new Honda power units for the Mexican Grand Prix.
Button is expected to drop 50 places in total as he will take a new ICE, turbocharger, MGU-H and MGU-K for first practice, before swapping it out for further replacements ahead of second practice.
This will give the Briton further options should he require a new engine at either the Brazilian or Abu Dhabi races, without incurring a further penalty.
Meanwhile Alonso will swap out his Austin engine for a brand new unit after it suffered damage. As a result, the Spaniard dropped out of the points last weekend after running in fifth place for much of the race.
He will drop ten places, but could face a further drop of five places if the team opt to change his gearbox, which will only be confirmed on Friday morning.
Both McLaren drivers will use the new ‘phase four’ engine which features revised injectors, which Honda identified as the cause of Alonso’s failure at the United States GP.
Due to a recent rule change, grid penalties can’t exceed the maximum number of grid spaces, therefore both drivers will likely start from the back of grid.