Engines and Components› Pistons and Piston Rings

Speed Pro

Piston Ring Set

$218.19

SKU: R9771-45

In Stock
In Stock
Ships by Sep 12
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$100 Minimum Order
30 Days Return
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Overview

The Speed Pro R9771-45 is a set of piston rings designed for enhanced performance. These rings feature a ductile iron top ring with a plasma moly facing for durability and quick seating. The second rings are made of cast iron with an oil-controlling taper face, and the oil rings are constructed from stainless steel for excellent oil control at high RPMs.
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The Speed Pro R9771-45 Plasma Moly Racing Rings are engineered to deliver increased horsepower and longevity. The top rings are constructed from high-strength ductile iron with a plasma moly facing, ensuring instant seating and extended wear life. Second rings are made from cylinder-friendly cast iron, featuring an oil-controlling taper face profile and an open gap design to minimize inter-ring pressure buildup. Exclusive electro-polished stainless steel SS50 oil rings prevent high RPM deflection, providing excellent oil control even at the highest engine speeds. These piston rings are designed for a universal 8-cylinder application with a bore size of 4.040” + .005” (4.045”). The top and second rings have a thickness of 1/16”, while the oil ring measures 3/16” with standard tension. They are file-fit, meaning they require gapping by the installer, and are sold as a set. The manufacturer is Federal Mogul, and the warranty is explicitly stated as "Race Application, No warranty expressed or implied."

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandSpeed Pro
Part NumberR9771-45
CategoryEngines and Components

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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