NGK Iridium IX TR6IX Spark Plugs for C6 Corvette 427 Convertible LS7
NGK Iridium IX TR6IX spark plugs, stock number 3689, fit the 2013 C6 Corvette 427 Convertible with the LS7 7.0L engine. This offer includes eight spark plugs supplied as two packs of four.
The 427 Convertible brings LS7 power to an open-top C6, and its service parts should follow that engine. This eight-plug set combines the quantity for all eight cylinders with fine-wire iridium construction designed for consistent ignition and electrode durability. Plan the plug replacement as an eight-cylinder service, then inspect the separate wires and coils rather than assuming they are included with the plugs.
Product Details
- NGK stock number: 3689; design code: TR6IX.
- Iridium fine-wire center electrode.
- Eight spark plugs: two packs of four.
- Spark plugs only; plug wires and ignition coils are not included.
- Plated steel shell: Trivalent metal plating provides corrosion protection on the threaded shell and helps with removal when the plugs are serviced again.
Benefits
- Complete V8 quantity: One order supplies all eight replacement plugs.
- Stable spark: The fine iridium tip supports consistent ignition and resists electrode wear.
- Thread protection: The plated shell helps resist corrosion and provides a release layer for later removal, without a separate anti-seize treatment.
Important Notes
- Fitment is the one-year 2013 427 Convertible Collector Edition with the 7.0L LS7.
- Confirm the supplied parts: Look for TR6IX and stock number 3689 on the replacement-plug packaging. Inspect the ceramic insulators and fine-wire electrodes before installation.
- Keep a service record: Note the replacement date, mileage and TR6IX identification with your 427 Convertible’s maintenance information. Use the vehicle’s applicable service guidance for future plug inspections.
- Confirm the installation gap and tightening specification for your exact vehicle. Do not assume the plug's supplied gap is the required setting.
- Protect the iridium tip: Use a round-wire or pin gauge to check the gap. Any adjustment should move the ground electrode without pressing or prying against the center electrode.
- No added thread lubricant: Fit NGK plugs dry, without anti-seize. Added lubrication changes the relationship between applied torque and the load on the plug.
- Correct tightening matters: An incorrectly tightened plug can have poor heat transfer or suffer damage. Follow the applicable service instructions, or use a qualified installer if the procedure is unfamiliar.
- Start with a cool engine: Clean the plug holes before fitting the new set. Debris can prevent full seating even when a torque wrench reaches its setting.
CORVETTE COMPATIBILITY
- 2013 C6 Corvette 427 Convertible
- LS7 7.0L engine, stock configuration
- Convertible
Why Buy from Custom Corvette Accessories?
At Custom Corvette Accessories, we’re Corvette owners ourselves, and we offer one-on-one customer service to help you choose parts for your car. Have a question about NGK 3689 TR6IX Iridium IX spark plugs for your 2013 C6 Corvette 427 Convertible LS7? Contact us for personal help before you order.
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