90.5 X 82 Piston & Cylinder Kit, Cast Pistons, 2110cc

OVERVIEW

Elevate your air-cooled engine build to the next level with the AA Performance 90.5mm x 82mm Piston and Cylinder Kit. Designed specifically for high-performance stroker applications, this kit is the heart of the legendary 2110cc engine configuration. The 90.5mm bore is widely considered the "sweet spot" for performance enthusiasts who refuse to sacrifice longevity. Unlike larger thin-wall cylinders, the 90.5mm barrels maintain a thick wall thickness at the top and bottom, which provides superior heat dissipation and structural integrity under high-compression loads. This ensures that your engine remains reliable whether you are cruising the local strip, carving through sand dunes in a rail, or pushing your Beetle through a spirited canyon drive. By utilizing a hypereutectic cast piston, this kit offers a tighter piston-to-cylinder clearance than forged alternatives, resulting in a quieter engine with less oil consumption and reduced blow-by during cold starts.

This specific "Stroker" or "B-Style" kit is engineered with a shorter compression height to accommodate long-stroke crankshafts ranging from 78mm to 84mm without the need for excessive barrel shimming. The inclusion of hypereutectic aluminum alloy pistons means you are getting a component that is significantly stronger than standard cast pistons, thanks to the high silicon content which provides excellent thermal stability and wear resistance. Every kit comes complete with four precision-honed cast iron cylinders, four hypereutectic pistons, high-quality piston rings, wrist pins, and circlips. Whether you are building a torquey street engine or a high-revving weekend warrior, AA Performance provides the tight tolerances and material quality required to ensure your Type 1 engine delivers smooth, consistent power for years to come. Don''t settle for mediocre displacement when you can harness the optimized balance of the 2110cc platform.

FITMENT

• Volkswagen Type 1: Beetle, Ghia (Requires engine case and cylinder head machining)
• Volkswagen Type 2: Bus, Transporter, Kombi (1600cc based engines only)
• Volkswagen Type 3: Fastback, Squareback, Notchback (Requires engine case and cylinder head machining)
• Custom Applications: Sand Rails, Dune Buggies, Trikes, and Kit Cars using Type 1 upright engine configurations
• Crankshaft Compatibility: Designed for 82mm stroke, but compatible with 78mm, 80mm, and 84mm stroker cranks
• Case Requirements: Must be bored to approximately 94.4mm to accept the 90.5mm cylinder spigots
• Head Requirements: Must be bored to approximately 98mm to accept the 90.5mm cylinder tops

TECHNICAL SPECIFICATIONS

• Engine Displacement: 2110cc (when used with an 82mm crankshaft)
• Piston Diameter: 90.5mm
• Cylinder Material: Cast Iron (Precision Honed)
• Piston Material: Hypereutectic Aluminum Alloy (Cast)
• Compression Height: 35mm (Stroker "B" Style)
• Wrist Pin Diameter: 22mm
• Ring Groove Sizes: 2.0mm Top, 2.0mm Middle, 4.0mm Oil Ring
• Cylinder Spigot Diameter (Bottom): 94.4mm
• Cylinder Head Bore (Top): 98mm
• Kit Includes: 4 Pistons, 4 Cylinders, 4 Wrist Pins, 8 Circlips, and Complete Ring Set

PRO TIPS FROM THE SHOP

1. Precision Machining is Mandatory

It is absolutely vital to understand that this is not a "drop-in" kit for a stock 1600cc engine. To run the 90.5mm cylinders, you must have your engine case and your cylinder heads professionally machined. The engine case needs to be opened up to 94.4mm and the heads to 98mm. We highly recommend sending your components to a dedicated VW machine shop that understands the specific tolerances required for air-cooled engines. Attempting to "hand-grind" or use improper tooling will result in a poor seal, leading to catastrophic oil leaks or overheating. Always dry-fit your cylinders into the case and heads before final assembly to ensure there is no binding and that the seating surfaces are perfectly flat and clean.

2. Critical Deck Height Measurement

When building a stroker engine like a 2110cc, checking your deck height is the most important step in the assembly process. Deck height is the distance from the top of the piston at Top Dead Center (TDC) to the top edge of the cylinder. Because this is a "B" style kit designed for long strokes, your geometry will change depending on your connecting rod length and crankshaft throw. We recommend a minimum deck height of .040" to .060" for a reliable street engine. If your deck height is too tight, you risk the piston hitting the head at high RPM; if it is too loose, your compression ratio will drop and your "quench" area will be inefficient. Use high-quality copper or aluminum barrel shims at the base of the cylinder to fine-tune this measurement perfectly across all four cylinders.

3. Proper Ring Gapping and Break-In

Never assume that piston rings are "pre-gapped" out of the box. Every high-performance build requires you to manually check the end gap of each ring inside the cylinder it will be living in. Use a feeler gauge to ensure the top ring has a gap of roughly .014" to .016" (consult a build manual for your specific application). If the gap is too tight, the rings will expand when hot, the ends will touch, and they will snap or gall the cylinder walls. Furthermore, because these are cast hypereutectic pistons, use a high-zinc break-in oil for the first 500 miles. Avoid synthetic oils during the initial break-in period, as they are too "slippery" and will prevent the rings from properly seating against the cylinder walls, which can lead to permanent oil consumption issues.