What is the function of the second compression ring?

The second compression ring is vital for controlling blow-by, which is unburned fuel and exhaust gases that leak past the piston. It also helps to scrape excess oil from the cylinder wall, preventing it from entering the combustion chamber.

Are these rings compatible with all engine builds?

These rings are designed as a direct replacement for specific engine applications. It's important to verify the bore size and other specifications match your engine's requirements before purchasing.

What does 'Not CARB approved' mean?

This means the product does not meet the emissions standards set by the California Air Resources Board (CARB). As a result, it cannot be legally shipped to or installed on vehicles registered in California.

Mahle OE Piston Rings 3021128

Name: Mahle Rings 4.7550 x .0857 PC479 THG 2nd Ring .170 RW Plain Ring Set
Brand: Mahle OE
SKU: mahle-oe-mahle-rings-4-7550-x-0857-pc479-thg-2nd-ring-170-rw-plain-ring-set-t14-50789
Price: 168.68 USD
Availability: BackOrder

Mahle Rings 4.7550 x .0857 PC479 THG 2nd Ring .170 RW Plain Ring Set

$168.68

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 Piston Rings. Part# 3021128. Direct fit.

Key Features

Mahle OE Piston Rings
Part Number: 3021128
Bore Size: 4.7550 inches
Second Ring Thickness: 0.0857 inches
Second Ring Width: 0.170 inches
Designed as a direct replacement for original equipment

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Product Details

If you're rebuilding the top end of your engine, getting the right piston rings is crucial for sealing combustion and managing oil. This set from Mahle OE is designed to fit specific applications, ensuring proper function for your engine's health. Mahle is a well-known name in engine components, and these rings are built to meet the demands of a rebuilt engine.

This particular ring set features a 4.7550 bore size with a .0857 inch thickness for the second ring, which is .170 inches wide. The second ring plays a key role in controlling blow-by and helping to scrape oil off the cylinder wall. Mahle uses solid materials and manufacturing processes to ensure these rings seat properly and maintain their tension against the cylinder wall for consistent performance. They are a direct replacement for the original equipment rings, meaning they are made to the same specifications.

When installing, always refer to your vehicle's service manual for the correct ring orientation and gap settings. Proper installation is key to achieving the best performance and longevity from your new engine components.