APR 2.5 TFSI Pistons

APR is pleased to present proprietary light-weight, high-strength forged OEM profile MAHLE pistons for 2.5 TFSI engines.

As the leader in high performance engine products for the Volkswagen Automotive Group, APR is capable of creating horsepower and torque levels outside of the original equipment’s stress tolerances. In such cases, it’s recommended and in some cases necessary to upgrade additional engine components to cope with the increased load. APR’s pistons raise the engine’s stress tolerance levels to provide years of continued reliable operation without compromise.

The introduction of direct injection played a significant role in piston combustion bowl design. The profile ultimately affects the swirl and tumble of the air/fuel mixture making the design critical for the most efficient use of the fuel. APR worked with MAHLE, a VAG Tier 1 supplier for OEM pistons, to design a proprietary piston sharing the OEM profile, as found in VAG’s higher performance 2.5 TFSI engines, along with other strength and weight saving properties.

Piston, wrist pin and rings

Quick Facts

  • Forged pistons
  • Proprietary APR / MAHLE design
  • Proprietary MAHLE 142S alloy
  • Low noise materials
  • Low thermal expansion for tighter tolerances
  • OEM piston compression bowl profile
  • 83mm oversized design
  • 10.1:1 compression ratio
  • MAHLE 22mm German tool steel wrist pins included
  • MAHLE low-drag rings included
    • Top - Barrel-Faced Steel (File to Fit)
    • Second - Tapered Face Ductil Iron (File to Fit)
    • Oil Rings - 3 Piece Standard Tension
  • 320 grams per piston
  • Hard anodized top ring grooves to prevent micro-welding
  • MAHLE proprietary Grafal anti-friction coated skirts
  • OEM oil squirter notches
  • First landing accumulator grooves for top ring seal promotion
  • Ultra flat ring grooves for ring seal promotion

The piston is designed to handle power levels far beyond the original component’s ratings in order to ensure reliability with years of continued use. Increasing piston strength often comes at the expense of increased weight, which ultimately reduces engine efficiency. To generate a balance between strength and weight, APR pistons are forged from MAHLE’s proprietary 142S alloy and treated with other MAHLE proprietary coatings. This material is stronger than the common 4032 alloy, provides quieter operation than 2618 alloy and maintains tighter piston to cylinder wall clearances thanks to the material’s low expansion rates. The piston’s grey phosphate coating acts as a dry lubricant to protect against galling and micro-welding while MAHLE’s proprietary Grafal skirt coating reduces drag, scuffing, friction, wear and noise.

To maintain the OEM piston profile, compression is raised roughly .1 due to the half mm overbore. APR’s engineering teams chose the 10.1:1 compression ratio after spending several years testing the affects on knock tolerance and off-boost operation from different ratios on VAG direct injection engines. APR explored altering the compression ratio, but were unable to locate any advantages in doing so.

APR pistons are designed for 83mm bore diameter, a half millimeter over the OEM units and as such are not drop in compatible. The larger piston diameter provides in an increased engine displacement from 2,480 cc to 2,511 cc. The slight increase in displacement and reduction in friction provided by the included high-performance, low-drag rings frees up horsepower. To remove any imperfections in the cylinder walls and to provide a new, compatible sealing surface for the upgraded rings, a first overbore must take place. APR does not recommend drop in pistons at this level of internal engine modification.

APR pistons include upgraded 22mm German tool steel wrist pins for ultimate strength and reliability.

The pistons are fully compatible with APR’s MS100070 connecting rods.


Piston Side Piston Bottom Piston Size CAD Drawings
APR Piston Application Guide
Engine Engine Codes Wrist Pin Weight Bore Part Number Price(税別)
Set of 4. Overbore and hone required.
2.5 TFSI CEP 22mm 320g 83 mm MS100069 ¥240,000

APR Tuned

Phone: (092) 883-9222 Fax: (092) 883-9213 Address: 1-18-3-101, Ikinomatsubara, Nishi-ku, Fukuoka, 819-0055

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