94mm x 82mm Forged Piston Set Set of 4

OVERVIEW

When you are building a high-performance air-cooled engine, the rotating assembly is the heart of your power plant, and these AA Performance Products 94mm x 82mm forged pistons are the gold standard for serious enthusiasts. Designed specifically for long-stroke "stroker" engines, these pistons feature a relocated wrist pin height (often referred to as "B" pistons) to accommodate an 82mm or similar long-throw crankshaft without the need for excessive cylinder shimming. Forging provides a significantly higher strength-to-weight ratio compared to traditional cast pistons, allowing your engine to withstand the increased cylinder pressures and higher RPM ranges associated with high-output 2332cc or 2276cc builds. Whether you are building a weekend bracket racer or a high-performance street Beetle, these forged slugs offer the thermal stability and structural integrity required to keep your engine running cool and strong under the most demanding conditions.

The 94mm bore is the largest common bore size for the Type 1 engine block, providing the maximum displacement possible while still maintaining enough cylinder wall thickness for reliable cooling. Because these are forged from high-quality 4032 aluminum alloy, they exhibit lower thermal expansion rates than 2618 alloy, meaning you can run tighter piston-to-wall clearances for a quieter engine and better oil control without sacrificing the durability needed for forced induction or high-compression naturally aspirated setups. This set comes complete with heavy-duty wrist pins and wire locks, ensuring that the connection to your connecting rods is as robust as the pistons themselves. When you choose AA Forged pistons from Appletree Auto, you are investing in a product that has been proven on the drag strip and the open dunes, providing the peace of mind that your vintage Volkswagen''s bottom end is built to last.

FITMENT

These pistons are designed for high-performance "Stroker" applications and require specific engine modifications. They are compatible with the following models provided the engine case and cylinder heads have been machined for 94mm cylinders:

• Volkswagen Type 1: Beetle, Bug, and Super Beetle (All Years).
• Volkswagen Type 2: Bus, Transporter, and Kombi (1950-1971 with Type 1 based engine).
• Volkswagen Type 3: Fastback, Squareback, and Notchback (All Years).
• Volkswagen Karmann Ghia: All Years.
• Volkswagen Thing: Type 181 (1973-1974).
• Custom Applications: Dune Buggies, Sand Rails, Trikes, and Kit Cars using VW Type 1 upright engine configurations.
• Note: These are "B" style pistons intended for 82mm and larger stroke crankshafts.

SPECS

• Piston Material: Forged 4032 Aluminum Alloy for superior strength and thermal characteristics.
• Bore Diameter: 94mm (Requires 94mm Bore Case and Heads).
• Stroke Compatibility: Optimized for 82mm stroke (Stroker "B" Type).
• Compression Height: Approximately 24mm (Reduced for long-stroke clearance).
• Wrist Pin Diameter: 22mm (Standard VW High Performance).
• Wrist Pin Material: Heavy-duty steel.
• Retainer Style: Wire locks (included).
• Set Quantity: 4 Pistons, 4 Wrist Pins, 8 Wire Clips.
• Manufacturer: AA Performance Products.
• Part Number: VW9400T1SPF.

PRO TIPS

Pro Tip 1: Precision Ring Gapping is Mandatory. Forged pistons expand differently than cast pistons, and while these 4032 alloys are more stable than other forged materials, you must still manually gap your piston rings. Always use a high-quality ring filer and check your gaps at the top of the cylinder where the bore is coolest. For a high-performance street engine, a general rule is .004 inches of gap per inch of bore diameter for the top ring, but always refer to your specific build sheet to prevent the ring ends from butting and causing catastrophic engine failure.

Pro Tip 2: Check Your Deck Height Twice. Because these are "B" pistons designed for an 82mm stroke, your deck height (the distance from the top of the piston to the top of the cylinder at TDC) is critical. Even with the relocated wrist pin, you may still need to use cylinder base shims to achieve the ideal deck height of .040 to .060 inches. Never assume the parts will bolt together with a perfect deck height; variations in case machining and rod length can significantly impact your compression ratio and valve-to-piston clearance.

Pro Tip 3: Proper Wrist Pin Lubrication. During assembly, don''t just slide the wrist pins in dry. Use a high-quality assembly lube or a 50/50 mix of engine oil and STP on the wrist pins and the small end of the connecting rod. Ensure the wire clips are fully seated in their grooves with the opening facing either 12 o''clock or 6 o''clock. This prevents centrifugal force from compressing the clip and allowing the pin to "walk" into the cylinder wall, which is a common cause of failure in high-RPM air-cooled engines.