Bosch 0242230806 (N40) Spark Plug Set of 4
Product description
What matters most
On the face of it, these are a set of four Bosch spark plugs designed to support reliable starts of a petrol engine and steady operation. The product is framed by Bosch’s long-standing ignition expertise, which suggests a focus on proven design and compatibility across a range of vehicles. If you prioritise a straightforward replacement that aligns with OEM-style reliability, this set offers a practical option to keep engines firing smoothly.
Practical fit and design
The specifications indicate 4 nickel alloy ground electrodes with a copper core, which is a common approach for efficient heat transfer and dependable ignition. The electrode gap is pre-set at 0.9 mm, and the thread length is 19 mm with a 14 mm size, featuring a spark position at 5 mm. This alignment means you don’t need to fiddle with gap adjustments during installation, which can save time and reduce the risk of improper setup when changing plugs.
How it performs on paper
On the surface, the design aims to promote steady acceleration and reliable operation by maintaining consistent combustion and heat management. The prescribed tightening torque of 28 Nm provides a clear guideline to achieve a proper seal without over-tightening. Bosch recommends using a torque wrench and avoiding lubrication on the thread, which matches standard maintenance best practices and helps prevent thread damage over time.
What you get and what to watch for
The pack contains four spark plugs, suitable for engines that require N40-class plugs. The product is presented with an emphasis on compatibility through the parts search function—an honest reminder that OEM-compatibility depends on the vehicle and engine requirements. If your car’s ignition needs align with this design, the set offers a convenient and consistent option for replacement.
Pros and cons in real-world terms
Pros: pre-set gap simplifies installation, copper core and nickel alloy ground electrodes support heat conduction and durability, clear torque guidance helps avoid installation mistakes, backed by Bosch’s ignition heritage. Cons: compatibility is vehicle-specific, if your engine requires a different plug type or heat range, this set may not be the right match. The description underscores compatibility checks, which means you’ll want to confirm your vehicle’s exact specification before buying.
Who this is for
This set is well-suited for motorists seeking a simple, reliable starter replacement for engines that match the N40-type design and who value a straightforward installation without tuning the gap. It can suit daily drivers and those performing routine maintenance where OEM-style parts are preferred.
When it makes sense to buy
If you’re replacing worn plugs in an appropriate engine and you value a design with a copper core for heat management and a pre-set gap for easier fitting, this Bosch set offers a practical route. It’s particularly sensible when you want to minimise guesswork during servicing and prefer established ignition technology.
When to look elsewhere
If your vehicle requires a different heat range, thread size, or gap, or if you need plugs with features beyond standard Ni–Cu construction (for example, special coatings or multi-electrode designs), this set may not be the best fit. Also, if you’re not comfortable verifying compatibility yourself, you may want impartial guidance to confirm fit.
What to check before buying
- Confirm your engine’s required spark plug type, heat range, and thread size match the N40 specification.
- Ensure you have access to a torque wrench to achieve the recommended 28 Nm tightening torque.
- Plan for standard replacement intervals and verify the vehicle’s owner manual for any manufacturer-recommended gaps or torque guidelines.
Practical use example
Imagine you’re performing a routine maintenance on a petrol car with a robust ignition system. You swap in the four Bosch plugs, follow the pre-set gap and torque recommendations, and you notice smoother starting after cold starts. The copper core helps with rapid heat dissipation during longer drives, which may translate to steady acceleration and consistent combustion on day-to-day trips.
FAQ (brief)
- Do these plugs come with a pre-set gap? Yes, the electrode gap is pre-set to 0.9 mm.
- Do I need to lubricate the threads? No, the guidance is to avoid lubricating the thread and to use a torque wrench.
- How many plugs are included in the pack? The set contains 4 spark plugs.
Final verdict
Is it worth it? Worth considering if your engine requires this N40-type plug and you value a straightforward, OEM-style replacement with consistent heat transfer and dependable ignition.