What is the spark plug gap on a Honda k20?
Typically 0.043–0.047 inches (1.1–1.2 mm). Always verify with your specific spark plug part and model year, as exact gaps can vary by plug design and vehicle configuration.
Context and significance
The spark plug gap is the distance between the center electrode and the ground electrode. On Honda's K-series engines, including the K20 family, the gap influences ignition timing, combustion stability, starting performance, and fuel efficiency. While many plugs are pre-gapped, ensuring the correct gap for your chosen plug type and model year is essential to prevent misfires and poor performance. This article outlines typical gap ranges and how to check or adjust them safely.
Typical gaps for Honda K20 engines
Below are the typical gap ranges you’ll encounter when servicing Honda K20 engines with common spark plugs. Exact figures depend on the plug type and model year; always confirm on the plug packaging or in the service manual.
- Standard/ OEM-style or common aftermarket iridium/platinum plugs: 0.043–0.047 in (1.1–1.2 mm)
- Some aftermarket iridium plugs may be pre-gapped to a similar range; if not, adjust to the plug’s specification
- In certain high-performance or different heat-range applications, gaps can be slightly narrower, around 0.040–0.043 in (1.0–1.1 mm); verify the exact plug’s spec
In practice, rely on the plug’s recommended gap and the vehicle’s service manual. Using a gap outside the recommended range can cause misfires, reduced power, or rough idling.
How to check and set the spark plug gap on a K20
To ensure the correct gap, inspect and adjust the gap with the proper tools before installation or reinstallation.
- Gather the tools: a spark plug gauge or a set of feeler gauges and a torque wrench or the torque spec from the manual
- Identify the correct plug type and the target gap from the packaging or Honda service literature
- Access the spark plugs by removing ignition coils or coil packs; carefully disconnect wiring
- Measure the gap with the gauge and compare to the target. If the gap is out of spec, adjust by carefully bending the ground electrode or using the gauge; avoid damaging the center electrode
- Reinstall the plugs and tighten to the OEM torque specification for your model year; reattach coils
These steps help ensure reliable ignition, smooth idle, and optimal performance for your Honda K20 engine.
Summary
The spark plug gap on most Honda K20 engines is typically 0.043–0.047 inches (1.1–1.2 mm). Always check the plug packaging and the vehicle’s service manual for your exact model year, as some plug designs or years may specify a slightly different gap. Properly gapped plugs and correct installation promote proper combustion and efficient operation.
For the latest specifications, refer to Honda’s official service manuals or the documentation accompanying your chosen spark plugs.
Are Honda NGK spark plugs pre-gapped?
Honda recommends replacement every 60k miles or sooner. These plugs are pre-gapped at . 044".
What is the best spark plug for a Honda GX390?
The NGK BP6ES/BPR6ES is the perfect Honda GX390 Spark Plug.
What is the best spark plugs for a Honda k24?
The best spark plugs for a K24 depend on the build, but for most applications, NGK Iridium are the top choice. For daily driving, use the factory-spec NGK laser iridium plugs, such as the ILZKR7B-11S. For forced induction (turbo/supercharger) or all-motor builds, a "colder" NGK iridium plug like the BKR9EIX is recommended to prevent detonation.
This video demonstrates how to replace spark plugs on a K24 engine: 1mThe Honda ResourceYouTube · Oct 16, 2021
For daily/stock engines
- Brand: NGK or Denso
- Type: Laser Iridium (the original equipment spec)
- Recommended part number: ILZKR7B-11S (check your specific vehicle for the correct part number)
- Gap: Do not gap, they come pre-gapped
For forced induction or high-performance builds
- Brand: NGK Iridium
- Type: A "colder" heat range plug is crucial
- Recommended part number: BKR9EIX for mild to high boost applications
- Gap: Do not gap these plugs, use them as they come from the factory
Installation tips
- Use anti-seize lubricant on the threads before installation.
- Apply dielectric grease to the inside of the coil packs before reattaching them.
- If you find oil in the spark plug wells, you will also need to replace the valve cover gasket and spark plug seals.
Does gapping spark plugs increase horsepower?
Side gapping spark plugs has been use in racing for years to increase horsepower by unshrouding the spark thus allowing the flame created to propagate faster resulting in a more complete burning of the fuel/air mix.
