Mahle 86.5mm or 87mm Pro Series piston set. These were developed to meet the demanding needs of professional racers and fast road applications. MAHLE Motorsports gives you a competitive edge with pistons that are meticulously finish prepared right out of the box. MAHLE machines the correct valve reliefs, dome profiles, and ring grooves for upper level competition

The pins are CNC machined with proper clearances, and every piston is hand deburred. Plus, with factory applied phosphate and GRAFAL© skirt coatings, you eliminate the expense and uncertainty of aftermarket coatings.

ProSeries features includes:

• Race proven quality pistons forged from 2618 aluminum alloy (the 2 barrel pistons are made form 4032)
• Ring grooves machined for light-weight low-drag racing ring packs
• Asymmetrical valve pockets
• Lateral gas ports for improved sealing, generating improved horsepower
• Precision milling for additional weight savings
• GRAFAL© anti-friction coating on skirts*
• Phosphate-coated to reduce micro-welding and pin galling**

* MAHLE?s GRAFAL© skirt coating - reduces drag, scuffing, friction and cylinder bore wear.

** Phosphate coating provides the grey appearance to the MAHLE piston. 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. The piston crown is still machineable.