Piston Ring Set, 87mm, 2 X 2 X 5, for Aircooled VW

Product Overview

When you are rebuilding your air-cooled powerplant, the integrity of your combustion seal is the single most important factor in determining horsepower and longevity. This Grant Piston Ring Set is specifically engineered for 87mm pistons, which are the industry standard for the popular 1641cc "slip-in" big bore kits. Grant has been a trusted name in the Volkswagen community for decades, providing high-quality cast iron and steel alloy rings that offer superior seating and heat dissipation. Whether you are refreshing a tired daily driver or assembling a crisp new street engine, these rings ensure that your compression stays in the combustion chamber and your oil stays in the crankcase. The 2mm by 2mm by 5mm configuration is the classic standard for 87mm pistons, offering a robust surface area that stands up to the thermal stresses inherent in an air-cooled environment.

Precision is everything when it comes to ring tension and gap clearances. These Grant rings are manufactured to exacting tolerances to ensure that they provide the perfect balance of cylinder wall pressure without excessive friction. By utilizing a high-quality oil control ring, this set minimizes oil consumption and prevents carbon buildup on your piston lands and valves. At Appletree Automotive, we know that air-cooled VW engines run hotter than their water-cooled counterparts, which is why we stock Grant ringsthey are designed to maintain their structural integrity and tension even under the high operating temperatures of a summer cruise or a long highway haul. Replacing your rings with this 87mm set is a cost-effective way to restore "like-new" snap and throttle response to your Type 1, Type 2, or Type 3 engine.

Vehicle Fitment

This ring set is designed for 87mm bore pistons (typically 1641cc engines) and fits the following models equipped with 1600cc-based upright or pancake engines:

• Volkswagen Type 1: Beetle and Super Beetle (1966-1977) equipped with 87mm Big Bore pistons.
• Volkswagen Type 1: Karmann Ghia (1966-1974) equipped with 87mm Big Bore pistons.
• Volkswagen Type 2: Bus / Transporter / Kombi (1963-1971) equipped with 1600cc based 87mm Big Bore kits.
• Volkswagen Type 3: Fastback, Squareback, and Notchback (1966-1973) with 87mm pistons.
• Volkswagen Type 181: Thing (1973-1974) with 87mm Big Bore pistons.
• Custom Applications: Dune Buggies, Sand Rails, and Trikes utilizing a VW 1600cc based engine case and 87mm pistons.

Technical Specifications

• Piston Bore Diameter: 87mm.
• Top Compression Ring Thickness: 2.0mm.
• Second Compression Ring Thickness: 2.0mm.
• Oil Control Ring Thickness: 5.0mm.
• Material: High-grade cast iron and steel alloy for maximum durability.
• Set Quantity: Complete set for four (4) pistons.
• OEM Reference: 311-198-16987.
• Manufacturer Part Number: Grant G1306.

Pro Tips from the Appletree Garage

1. Proper Ring Gap Staggering is Vital

One of the most common mistakes during engine assembly is failing to properly clock the piston ring gaps. You should never align the gaps of the top, second, and oil rings. Ideally, you want to space the gaps 120 degrees apart around the circumference of the piston. This creates a "labyrinth" seal that makes it much harder for combustion gases to blow by the rings into the crankcase. Always double-check your gap orientation right before you slide the cylinder over the piston, as the rings can sometimes rotate during the handling process. Ensuring they stay staggered will maximize your engine''s initial compression and overall efficiency.

2. Always Hone Your Cylinders

Never install brand-new rings into a "glazed" or shiny cylinder wall. If you are reusing your 87mm cylinders, you must use a cylinder hone to create a fresh cross-hatch pattern (roughly a 45-degree angle). This microscopic roughness is what allows the new rings to "seat" properly. Without this cross-hatch, the rings will simply skitter across the surface, failing to wear into the wall correctly, which leads to permanent oil burning and poor compression. After honing, clean the cylinders thoroughly with hot soapy water and a white lint-free cloth until no grey residue remains, then immediately coat them with a thin layer of engine oil to prevent flash rusting.

3. Verify Your Ring Orientation

Grant rings, like most high-quality VW rings, often have a specific orientation. Look closely at the flat surface of the compression rings for a small "Top" mark or a dimple. This mark must always face toward the combustion chamber (upward toward the cylinder head). If the rings are installed upside down, the taper or chamfer on the ring will actually act as a pump, pulling oil into the combustion chamber instead of scraping it down into the case. Additionally, use a dedicated piston ring expander tool for installation; using your fingers can easily over-stress the cast iron material, leading to invisible micro-fractures that cause the ring to snap once the engine reaches operating temperature.