Mercedes “bullish” on F1 engine reliability progress, says McLaren

The German manufacturer was locked in a tight title battle with Red Bull throughout 2021, but had to endure a run of grid penalties in the closing stages of the campaign amid concerns about the durability of its power units.

The rules limited teams to a total of three major power unit components for the entire season, but both Mercedes drivers had to take a number of new parts.

Valtteri Bottas used a total of six internal combustion engines during the season, the most of any…