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Forged Piston Set [Mk3 Focus RS]

The mountune Forged Piston Set for mk3 Focus RS EcoBoost has been designed as a high-performance upgrade for those wanting the ultimate piston for reliable, high-power builds.

This latest iteration has been co-developed with Mahle Motorsport to offer additional strength in key areas and also uses many of the design features that have been developed and proven in our highest performing racing engines.

The forged pistons are manufactured in the US by MAHLE Motorsport, utilising its 4032 grade alloy. This alloy was chosen for not only for its strength and durability, but also because of its high-silicone content and low-expansion properties.

This means that a tighter piston to bore clearance can be used, which will result in a tighter seal and less noise when the engine is cold.

The forged pistons also feature a distinctive grey phosphate coating. This dry lubricant coating (not to be confused with a thermal film coating) provides a lubricant film in the pin bores and ring grooves until the oiling system of the engine reaches operating pressure; particularly useful during the initial start-up or break-in of engines to protect against galling and micro welding.

In addition to this, the piston skirts have also been treated with MAHLE's patented Grafal coating to reduce drag and friction in the cylinder bore, and also help to reduce some of the noise often associated with forged pistons.


  • Co-developed by mountune Racing
  • Manufactured by MAHLE Motorsport
  • 22.5mm Gudgeon pin
  • Forged from 4032 grade aluminium alloy for optimum strength
  • CNC machined piston crown and pin bores
  • MAHLE Grafal anti-friction coating on skirt to reduce drag, scuffing, cylinder bore wear and noise
  • Phosphate-coated to reduce micro-welding and pin galling
  • High strength lightweight steel gudgeon pins
  • Race-proven round wire locks
  • Low drag piston ring pack.

    Please note: Sold as a set of four pistons.