MAHLE Performance Napier Steel Second Compression Ring 3.917in Bore 1.2mm
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This item may be on backorder. Please contact us to confirm supplier availability and estimated lead time before ordering.
Regular price
$114.04
Verified Fitment & Application Support
This product is selected for proper fitment and compatibility with the listed engine application. Our team is available to assist with fitment questions, installation considerations, and supporting components to ensure a smooth install and reliable performance.
Got Questions? Feel free to email us or call us at (503) 235-1947
Compliance & Restrictions
California Proposition 65 (Prop 65)
WARNING: This product can expose you to chemicals which is known to the State of California to cause cancer and/or reproductive harm.
For more information, visit www.P65Warnings.ca.gov.
CARB / California Emissions Compliance
This item may be restricted in California and other regions with emissions regulations. If applicable, it is intended for
competition/off-road use only unless otherwise stated. It is the customer’s responsibility to confirm local compliance before purchase.
Orders shipping to restricted areas may be canceled.
A second compression ring from MAHLE's open-stock performance ring program, sized for 3.917in bore at 1.2mm axial height. It is built from SAE 9254 steel.
Key Features
- Second ring duty is roughly 80% oil control and up to 20% compression control
- SAE 9254 high alloy steel provides the tensile strength, hardness and fatigue resistance needed at high cylinder pressure, and its strength allows a lighter cross section that conforms better to an imperfect bore.
- The Napier tapered hook groove profile scrapes oil from the cylinder wall on the downstroke and rides on an oil film on the upstroke. It also acts as a check valve, relieving combustion pressure that builds under the top ring and helping keep that ring stable.
Product Details
- Brand: MAHLE Performance
- Product type: Second Compression Ring
- Bore diameter: 3.917 in
- Axial height: 1.2mm
- Radial wall thickness: .135 in
- Base material: SAE 9254 steel
- MAHLE ring type: THM-13
- Position: Lower compression ring (second)
- Manufacturer Part Number: 302-1299
Shipping Height: 3.25
Shipping Length: 5.0
Shipping Width: 5.0