Mahle has responded to your demanding requirements for a reliable and strong 2.5L 5 cylinder piston. Great for high boost applications, these pistons are engineered for high thermal loads, fast engine speeds with demanding inertia load, and designed to deal with ignition pressure stress unique to direct fuel injection and turbocharging. These weight-optimized forged pistons are manufactured from high-temperature resistant aluminum-silicon alloy. This alloy along with Mahle's production technology combine for an ideal piston for race and street use.
These piston sets include high-quality 22mm diameter German steel wrist pins and wire locks. Strenuous testing of multiple pin sizes on this piston and engine combination has determined the 22mm pin is ideal for weight, strength, and durability. To match these pistons, a 2.5L specific connecting rod with a non-tapered 22mm small-end is required. IE offers industry-leading performance Tuscan connecting rods (IERTVB1) that are a direct fit and perfect match for your 2.5L 5 cylinder bottom-end build.
Mahle pistons are treated with their own coating known as GRAFAL. GRAFAL skirt coating greatly reduces the skirt to wall surface friction and increases scuffing resistance. Another advantage of the GRAFAL coated pistons is they enable a closer fitting clearance that gives significantly lower engine noise in conjunction with complex piston forms.
These pistons are manufactured from Mahle’s proprietary 142P alloy. This unique alloy offers the low-expansion characteristics of 4032 but strength near that of 2618 alloy. The low-expansion quality allows piston-to-wall clearances to be set tight, which allow the pistons to operate like OEM, quietly and smoothly.
Included is a set of performance piston rings, featuring a barrel-faced top ring, ductile iron, and 3 piece oil ring. These rings are designed to eliminate unnecessary drag, which reduces friction and increases power. To maximize power output, the clearances between the rings and piston have been brought in very tightly to reduce blow by. This is achieved by hard anodizing the top ring lands, which prevents micro welding which could be caused otherwise. Beneath the top ring and second ring lands an accumulator groove is machined, which provides a cavity where blow-by gasses can collect. This reduces pressure between rings, while virtually eliminating ring flutter and keeps top rings sealed securely against the bores.