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Champion 304 RS9YC Copper Plus Spark Plug 4-Pack

Manufacturer

Champion

<h3>Champion: A Legacy of Engine Performance</h3><p>For decades, <strong>Champion</strong> has been one of the most trusted names in engine ignition and maintenance. Born from a commitment to precision engineering, Champion has earned its reputation by delivering reliable, time-tested replacement parts that keep engines running at their best — whether on the road, on the water, or in the backyard.</p><h3>World-Class Spark Plug Technology</h3><p>Champion's story is inseparable from the spark plug. The brand helped pioneer modern ignition technology, and today its spark plug lineup remains a go-to choice for automotive technicians and DIY mechanics alike. Champion <a href="/120-champion-spark-plug-7212">spark plugs</a> are engineered to deliver consistent ignition performance across a wide range of engine types, from daily-driver commuter cars to high-demand power sport machines. Whether you're tuning up a classic V8 or maintaining a small-displacement four-cylinder, Champion offers a plug designed to match your engine's specific requirements.</p><p>Beyond the plug itself, a reliable ignition system depends on every component working in harmony. Champion's <a href="/120-champion-spark-plugs-spark-plug-boot-kit-23507">spark plug boot kits</a> provide the complete solution — protecting ignition wires and ensuring a secure, interference-free connection between the plug and the ignition system. These kits are especially popular for vehicle owners who want a thorough tune-up rather than a partial fix.</p><h3>Marine and 2-Cycle Engine Solutions</h3><p>Champion's expertise doesn't stop at automotive ignition. The brand also serves boaters and marine enthusiasts with products formulated for the unique demands of water-based engines. Champion <a href="/120-champion-2-cycle-outboard-oil-200042">2-cycle outboard oil</a> is designed to protect outboard motors running in demanding marine conditions, helping to minimize wear, reduce deposits, and extend engine life. It's a natural extension of Champion's core philosophy: give every engine — regardless of application — the quality it deserves.</p><h3>Built for Every Engine, Every Application</h3><p>What sets Champion apart is the breadth of its coverage. From passenger vehicles to boats, lawn and garden equipment to power sport machines, Champion engineers products with real-world performance in mind. The brand's catalog of over 800 products means that regardless of what you drive, ride, or operate, there's a Champion part designed to keep it running at peak efficiency.</p><p>Whether you're doing a routine tune-up or a full ignition system overhaul, Champion's combination of heritage, innovation, and comprehensive coverage makes it a brand worth turning to first.</p>

Part Number

304
06/01/2036 12:55 AM
Sale Price

$3.68

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Champion 304 RS9YC is a conventional spark plug featuring nickel alloy electrodes and a copper core center electrode that provides increased conductivity and heat control for good overall wear. The extruded copper core in the center electrode maintains accurate control of heat range, optimizing the performance and longevity of the spark plug.

Key Specifications:

  • Thread Size: 14mm (9/16") with 1.25mm (1/16") pitch
  • Seat Type: Tapered
  • Reach: 0.689" (17.5mm)
  • Hex Size: 5/8" (16mm)
  • Gap: 0.035" (0.9mm)
  • Terminal Type: Removable Nut
  • Resistor Type: SAC-9
  • Heat Range: 9

Performance Features:

  • Patented SAC-9 semi-conductor resistor for maximum EMI & RFI suppression
  • Built to ISO and SAE standards for proven performance
  • TinTac and ULTRASEAL shell for best corrosion protection
  • 20,000 mile longevity rating

Installation torque: 7-15 lb-ft for cast iron or aluminum heads. This spark plug fits Indmar, Marine Power, Mercury Marine, OMC, Pleasurecraft Marine, and Volvo Penta engines. Replaces OEM part number 3851869.

Products specifications

Manufacturer Part Number

304

Model Number

RS9YC

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Just ordered first time . so far so good

Competitive pricing and fast shipping

As advertised

easy to understand

All seems great. Had item in stock as on there website and it was shipped quickly.

I received my Borgeson steering shaft today for my 1990 dodge 1st gen. This is where I found the lowest price for the product. I was also very pleased in the speedy delivery. I will definitely use this company again.

Really impressed with speedy order to customer service,also some of the best savings online.Ordered parts late Monday, got the parts wednesday afternoon, combined savings of about $20.00 over nearest low price online. Thanks for the savings, will be ordering from you soon.

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