Sierra 18-8820-1 Premium Marine Spark Plug Wire Set
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Within 30 days
Sierra 18-8820-1 Premium Marine Spark Plug Wire Set Product Description
Engineered for Unmatched Marine Performance
Upgrade your boat's ignition system with spark plug wires that stand up to the relentless demands of saltwater, humidity, and high-revving action. These premium wires deliver reliable starts, smoother idling, and peak horsepower by ensuring every spark is strong and consistent. Unlike basic replacements, they suppress radio frequency interference (RFI) to keep your electronics—GPS, fish finders, and stereos—running interference-free.
Core Innovations That Set Them Apart
- Magnetic suppression core: Tailored precisely for marine engines, it minimizes electrical noise for cleaner signals and better overall system harmony.
- Kevlar core: Offers bulletproof strength against abrasion, stretching, and fatigue, outlasting standard conductors in brutal marine conditions.
- Stainless steel wound conductor: Boosts conductivity for maximum power transfer, firing plugs with precision even under heavy load.
- High-temp silicone jacketing and boots: Shields against extreme heat from exhaust manifolds and engine bays, preventing breakdowns during long runs.
- Corrosion-resistant terminals: Stainless steel construction fights rust from saltwater spray, maintaining top conductivity season after season.
- OE-style boots: Create a tight seal to block out moisture, grit, and contaminants that plague exposed marine wiring.
Designed specifically for Thunderbolt-type ignition systems, these wires integrate seamlessly, restoring factory-level performance while exceeding it in durability.
Why Marine Enthusiasts Demand These Wires
In the marine world, weak spark plug wires lead to misfires, lost power, and frustrating breakdowns far from shore. These premium sets tackle that head-on with superior RFI suppression, vital for boats packed with sensitive nav gear and digital gauges. Expect crisper throttle response, reduced fuel waste, and engines that roar to life on the first crank—every time.
Boat owners report fewer tune-ups and longer intervals between replacements, thanks to materials built for wet, salty environments. Whether you're trailering to tournaments, chasing offshore species, or cruising family weekends, these wires keep you powered without compromise.
Real-World Edge Over Stock Wires
"Switched to these after standard wires failed mid-run. No more static on VHF, and the engine pulls harder than new."
The stainless steel terminals and silicone insulation laugh off corrosion that eats through lesser options, while the Kevlar core shrugs off the flexing and vibration of rough seas.
Effortless Swap for DIY Mechanics
Installing these wires is straightforward, mimicking original equipment design for a plug-and-play experience. Start by marking wire positions on your distributor cap to avoid mix-ups. Gently twist and pull old wires free, noting any brittle boots—a common failure sign.
- Clean terminals and plugs for optimal contact.
- Route new wires following factory paths to dodge heat sources.
- Push boots firmly onto plugs and distributor until seated—listen for the snap.
- Test-fire the engine, checking for smooth operation and no codes.
Pro tip: Apply dielectric grease sparingly to terminals for extra moisture protection. Most swaps take under an hour, no special tools needed beyond basics.
Maximize Longevity in Harsh Waters
Regular checks keep these wires firing strong. After every outing, inspect boots for cracks or looseness. Rinse salt residue with fresh water post-brine exposure, and avoid high-pressure washers near connections. In storage, coil wires loosely to prevent core stress.
Signs of wear include rough idling, RFI noise in radios, or visible boot hardening. Proactive replacement every 2-3 seasons ensures peak reliability, far outpacing generic alternatives.
Frequently Asked Questions
What sets marine spark plug wires apart from automotive ones?
Marine wires prioritize waterproofing, corrosion resistance, and RFI suppression due to saltwater exposure and onboard electronics. These feature silicone boots and stainless terminals built for constant moisture.
Are these compatible with Thunderbolt ignition systems?
Yes, engineered specifically for Thunderbolt-type ignitions, ensuring perfect fit and performance without modifications.
How do Kevlar cores improve durability?
Kevlar resists stretching, cutting, and heat degradation far better than copper strands, ideal for vibrating engines and tight bilge spaces.
Will these reduce radio interference on my boat?
Absolutely—the magnetic suppression core excels at RFI control, keeping VHF, depth finders, and stereos crystal clear even at WOT.
What's the best way to store my boat with these wires installed?
Disconnect the battery, spray terminals with corrosion inhibitor, and cover the engine to shield from humidity. Inspect annually before launch.
Can silicone jacketing handle engine bay heat?
Yes, rated for extreme temps up to 500°F+, protecting against exhaust proximity and prolonged high-RPM runs.
Do I need to replace all wires at once?
For best results, yes—mismatched wires can cause uneven firing and reduced efficiency. A full set restores balance.
- Magnetic Suppression Core manufactured for your specific application.
- Kevlar® core for maximum durability and long life
- Durable stainless steel wound conductor for maximum horsepower and engine performance
- Premium silicone jacketing and boots for the ultimate in high temperature protection
- Superior RFI suppression for the most sensitive electronic system
- Corrosion resistant stainless steel spark plug and distributor terminals for maximum conductivity
- OE style boots provide a sealed barrier against heat, dirt and moisture
- Thunderbolt type ignition
Save $23 when you buy the Sierra 18-8820-1 Premium Marine Spark Plug Wire Set for only $74 from NVN Marine! Same day shipping before 3pm.
Sierra 18-8820-1 Premium Marine Spark Plug Wire Set Technical Specifications
| Type: | |
|---|---|
| Vendor: |
Sierra Engine Parts |
| Weight: |
1.99 lb |
| Application: |
Flagship, Indmar, Marine Power & Mastercraft - 350, 5.7L, 454, 7.4L, 502, 8.2L, 8 cylinder, EST, EFI ignition |
| OEM #: |
- |
Sierra 18-8820-1 Premium Marine Spark Plug Wire Set User Reviews
Sierra 18-8820-1 Premium Marine Spark Plug Wire Set Shipping & Return
| Shipping Weight: |
1.99 lb |
|---|---|
| Box Sizes: |
2.00 (h) x 7.00 (w) x 10.00 (l) |
| Cubic Feet: |
140.0 |
| Returnable: |
Yes |
For detailed shipping policy please check our Shipping Policy and you can find our Return and Refund Policy here.