What is a Napier style second ring?

A Napier style second ring has a unique shape that helps it to scrape oil from the cylinder wall more effectively. This design also contributes to good compression sealing, making it a popular choice for performance engines.

What does 'Reduced Wall' mean for these rings?

Reduced Wall (RW) typically refers to a ring design where the back of the ring is tapered or shaped to reduce its overall thickness or weight. This can help with sealing and reduce drag.

Can these rings be shipped to California?

No, these rings are not CARB approved and cannot be shipped to California due to emissions regulations.

Mahle OE Piston Rings 3021221B - Performance Napier Steel

Name: Mahle Rings Perf Napier Steel 2nd Ring 4.135in x 1.0MM .136in RW Plain Ring Set (48 Qty Bulk Pack)
Brand: Mahle OE
SKU: mahle-oe-mahle-rings-perf-napier-steel-2nd-ring-4-135in-x-1-0mm-136in-rw-plain-r-t14-48442
Price: 237.29 USD
Availability: BackOrder

Mahle Rings Perf Napier Steel 2nd Ring 4.135in x 1.0MM .136in RW Plain Ring Set (48 Qty Bulk Pack)

$237.29

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 Performance Napier Steel 2nd Ring Set. Bulk pack of 48 rings, not CARB approved.

Key Features

This is a bulk pack containing 48 Mahle OE performance Napier steel second rings.
Each ring is designed for a 4.135-inch bore size.
The rings have a 1.0mm thickness and fit a .136-inch ring groove.
Features a Reduced Wall (RW) Plain Ring design for improved sealing.
Steel construction offers good durability for performance applications.
Not CARB approved; cannot be shipped to California.

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Product Details

Mahle OE is known for making solid engine components, and this bulk pack of 48 performance Napier steel second rings is no exception. These rings are designed for a 4.135-inch bore and feature a 1.0mm thickness with a .136-inch groove width, specifically a RW (Reduced Wall) Plain Ring design. This type of ring is often chosen for its ability to seal well under demanding conditions.

The Napier style of second ring is a popular choice because its shape helps to scrape oil from the cylinder wall more effectively than a standard ring, while also providing good compression sealing. The steel construction offers durability, and the specific dimensions are critical for proper engine rebuilds where precise tolerances are key. Because these are sold in a bulk pack of 48, they are ideal for shops or builders working on multiple engines or high-performance builds that require many sets.

Keep in mind that these rings are not CARB approved and cannot be shipped to California. Always refer to your engine's specific service manual for installation procedures and recommended ring gap settings.