94mm x 82mm Hypereutectic Pistton Set, Set of 4

OVERVIEW

When it comes to building a high-displacement air-cooled powerhouse, the 94mm bore is the gold standard for those seeking maximum displacement and power. This AA Pistons hypereutectic piston set is specifically engineered for 82mm stroker applications, providing the ideal "B-style" compression height to keep your deck height manageable without the need for excessive and cumbersome shimming. Unlike standard cast pistons, the hypereutectic alloy used in these pistons contains a higher silicon content, which significantly reduces thermal expansion. This unique material property allows engine builders to run tighter piston-to-wall clearances, resulting in a quieter engine during cold starts, superior oil control, and improved longevity for high-performance street builds. Whether you are aiming for a 2276cc or a 2332cc beast, these pistons offer the structural integrity needed to handle increased cylinder pressures while maintaining the streetability that air-cooled enthusiasts crave.

This comprehensive set includes four precision-machined pistons, high-quality wrist pins, and heavy-duty circlips, ensuring you have the core components ready for your next bottom-end assembly. AA Pistons has built a reputation in the Volkswagen community for delivering race-proven technology at an accessible price point, and this 94mm x 82mm set is no exception. The "B" style compression height is the critical factor here, moving the wrist pin location closer to the piston crown to compensate for the longer throw of an 82mm crankshaft. By choosing hypereutectic over traditional forged pistons for a daily driver or weekend cruiser, you benefit from a piston that doesn''t "slap" when the engine is cold, yet remains incredibly resistant to the high temperatures generated by performance air-cooled heads. It''s the perfect balance of durability and refinement for the serious VW builder who demands reliability alongside high-horsepower output.

FITMENT

This piston set is designed for high-performance Volkswagen Type 1 based engines utilizing 94mm cylinders and an 82mm stroker crankshaft. Common fitment includes:

• Volkswagen Beetle (Type 1): All years utilizing a 94mm bore and stroker crank.
• Volkswagen Karmann Ghia: Performance builds with upgraded engine cases.
• Volkswagen Bus (Type 2): 1600cc based upright engines converted to stroker displacements.
• Volkswagen Thing (Type 181): Off-road or street performance stroker builds.
• Dune Buggies & Sand Rails: Ideal for 2276cc or 2332cc engine configurations.
• Custom Air-Cooled Kits: Any Type 1 engine case machined for 94mm cylinders and clearanced for an 82mm stroke.

SPECS

• Piston Diameter: 94mm
• Stroke Compatibility: Optimized for 82mm (B-Style Compression Height)
• Material: High-Silicon Hypereutectic Aluminum Alloy
• Wrist Pin Diameter: 22mm (Standard VW Performance)
• Set Quantity: 4 Pistons, 4 Wrist Pins, 8 Circlips
• Compression Height: Approximately 24mm (Stroker Height)
• Engine Displacement Potential: 2276cc (with 82mm crank)
• Weight: Weight-matched in sets for balanced engine operation
• Thermal Expansion Rate: Low expansion for tighter tolerances

PRO TIPS

1. Critical Ring Gapping for Hypereutectic Alloy

Because hypereutectic pistons contain high levels of silicon, they retain more heat in the crown than standard cast pistons. This means the top piston ring will experience higher temperatures and more thermal expansion. It is absolutely vital that you check and set your ring gaps according to AA Pistons'' specific recommendations for hypereutectic sets. A gap that is too tight can cause the ring ends to butt together as the engine reaches operating temperature, which can lead to broken ring lands or catastrophic cylinder wall damage. Always "file-fit" your rings to ensure your high-performance engine has the room it needs to breathe and expand safely.

2. Precise Deck Height Measurement

When building a stroker engine with 94mm x 82mm dimensions, your deck height is the most important measurement for both cooling and performance. Even with the "B-style" compression height of these pistons, you must mock up the assembly without rings first. Use a deck height gauge to measure the distance from the top of the piston to the top of the cylinder at Top Dead Center (TDC). Aim for a deck height between .040" and .060" for a street engine. If your deck is too tight, you risk the piston hitting the head at high RPM; if it''s too loose, you''ll lose quench effect, which can lead to overheating and detonation. Use high-quality copper or aluminum base shims to dial this in perfectly.

3. Proper Wrist Pin Clip Orientation

During assembly, pay close attention to the orientation of the wrist pin circlips. A common mistake that ruins high-end builds is improper clip installation. Always install the clips with the "opening" or gap facing either 12 o''clock or 6 o''clock (relative to the piston crown). This prevents the inertial forces of the piston''s high-speed travel from compressing the clip and allowing it to pop out of its groove. Additionally, ensure the clips are fully seated in the groove by giving them a slight rotation once installed. If a clip isn''t seated, it can migrate out and score your expensive 94mm cylinder walls beyond repair.