What is a Napier hook design on a piston ring?

A Napier hook design is a specific shape on the top piston ring. It helps the ring maintain a consistent seal against the cylinder wall and also aids in scraping oil from the cylinder wall during the piston's downstroke. This improves oil control and reduces blow-by.

What is the advantage of steel piston rings?

Steel piston rings are chosen for their strength and wear resistance compared to cast iron. This makes them a good choice for performance applications or engines that experience higher operating temperatures and pressures, contributing to longer ring life.

What does '48 Qty Bulk Pack' mean?

This means the package contains 48 individual piston ring sets. This is typically intended for professional engine builders or machine shops that work on multiple engines requiring this specific ring size and type.

Mahle Performance Piston Rings THM-13 3021252B

Name: Mahle Rings Performance Steel Napier THM-13 4.035 x .043 .135 RW Plain Ring Set (48 Qty Bulk Pack)
Brand: Mahle OE
SKU: mahle-oe-mahle-rings-performance-steel-napier-thm-13-4-035-x-043-135-rw-plain-ri-t14-47714
Price: 315.67 USD
Availability: BackOrder

Mahle Rings Performance Steel Napier THM-13 4.035 x .043 .135 RW Plain Ring Set (48 Qty Bulk Pack)

$315.67

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 Steel Piston Rings. THM-13, 4.035" bore, .043/.135 ring sizes. Bulk pack of 48.

Key Features

Fits 4.035 inch bore engines.
Features a Napier hook design on the top ring for improved oil control and sealing.
Top ring thickness is .043 inches.
Oil ring thickness is .135 inches.
Constructed from steel for strength and durability.
Comes in a bulk pack of 48 rings.

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Product Details

This is a bulk pack of 48 Mahle OE Performance Steel Piston Rings, specifically the THM-13 series. These rings are designed for a 4.035-inch bore with a .043-inch top ring and a .135-inch oil ring. They feature a Napier hook design on the top ring, which helps improve oil control and reduce blow-by, especially in performance applications. This set is well-suited for engine rebuilds where consistent sealing and durability are important.

Mahle is a well-known name in engine components, and these rings are built with steel for strength and wear resistance. The Napier hook design is a notable feature that helps the top ring maintain a consistent seal against the cylinder wall, even under demanding conditions. This design also aids in scraping oil from the cylinder wall, contributing to better lubrication and reduced oil consumption. This bulk pack is ideal for shops or builders who frequently work on engines requiring this specific ring size and configuration.

When rebuilding an engine, selecting the right piston rings is crucial for proper cylinder sealing, oil control, and overall engine performance. These Mahle rings offer a solid option for builders looking for reliable steel rings with a performance-oriented Napier design.