What is a Napier second ring and why is it used?

A Napier second ring has a unique shape that helps it scrape oil off the cylinder wall more effectively than a standard ring. This design is often chosen for its ability to improve oil control and reduce oil consumption, especially in engines that experience high cylinder pressures or operate under demanding conditions.

What does the '4.630 Bore' specification mean?

This specification indicates the diameter of the cylinder bore that these piston rings are designed to fit. For these rings, the cylinder bore must measure exactly 4.630 inches for proper sealing and function.

What is the advantage of buying a bulk pack of 48 sets?

A bulk pack is cost-effective for engine builders, repair shops, or anyone working on multiple engines simultaneously. It ensures you have enough sets on hand for a large project or for future needs without having to purchase individual sets repeatedly.

Mahle OE Piston Rings 3021202B - 4.630 Bore

Name: Mahle Rings Steel Napier THM-13 4.630 Bore x .043in .135 RW Plain Ring Set (48 Qty Bulk Pack)
Brand: Mahle OE
SKU: mahle-oe-mahle-rings-steel-napier-thm-13-4-630-bore-x-043in-135-rw-plain-ring-se-t14-47438
Price: 518.36 USD
Availability: BackOrder

Mahle Rings Steel Napier THM-13 4.630 Bore x .043in .135 RW Plain Ring Set (48 Qty Bulk Pack)

$518.36

On Backorder

Order now to reserve yours — we'll ship as soon as stock arrives. Full refund if we're unable to fulfill.

Mahle OE Steel Napier Piston Ring Set for 4.630 inch bore. Bulk pack of 48 sets.

Key Features

Fits engines with a 4.630 inch bore.
Features a .043 inch thick top ring and a .135 inch Napier second ring for improved oil control.
Constructed from durable steel for good wear resistance and sealing.
Bulk pack includes 48 individual piston ring sets.
Designed for engine rebuilding and performance applications.
Mahle OE quality ensures reliable performance.

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Product Details

When you're rebuilding an engine, especially for a performance application or a fleet of vehicles, getting the piston rings right is critical for sealing and oil control. This bulk pack of Mahle OE Steel Napier THM-13 ring sets is designed for a 4.630 inch bore and features a .043 inch top ring thickness with a .135 inch Napier second ring. The Napier ring is a popular choice because its shape helps scrape oil off the cylinder wall more effectively, which can lead to improved oil control and reduced oil consumption, especially in high-performance or heavy-duty scenarios.

Mahle is a well-known name in engine components, and these rings are made from steel, offering good durability and resistance to wear. The steel construction helps them maintain their shape and sealing ability under the stress of combustion. This particular set is a bulk pack containing 48 individual ring sets, making it a practical and cost-effective solution if you're working on multiple engines or a large project. The .043 inch top ring is a common size that works well with many piston designs, and the overall design aims for solid sealing to maximize compression and power.

Because this is a bulk pack, it's ideal for engine builders, repair shops, or anyone undertaking a significant engine overhaul. While these rings are built for performance and durability, please note they are not CARB approved and cannot be shipped to California. Always refer to your specific engine's service manual for detailed installation procedures and specifications to ensure proper fitment and function.