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NGK ZFR6FIX-11 Iridium IX Spark Plug (6441)
Original price was: £22.62.£12.82Current price is: £12.82.
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NGK Iridium IX Spark Plug – ZFR6FIX-11 (Stock No. 6441)
This NGK Iridium IX plug delivers a strong, consistent spark for better throttle response and smoother running. The fine-wire iridium tip needs less voltage to fire, which helps cold starts and reduces misfires. It is a durable upgrade over standard copper plugs.
Use it as a performance-focused replacement where ZFR6F-11 is specified. Always confirm fitment with the vehicle lookup or check the Vehicle Fitment tab.
- Sharper ignition and smoother idle
- Improved cold starting and response
- Long service life compared to standard plugs
Do not force-adjust the electrode gap on iridium fine-wire plugs.
| Part Category | 686 – Spark Plug |
| Part Number | ZFR6FIX-11 |
| NGK Stock Number | 6441 |
| GTIN | 087295164419 |
| Plug Type | Iridium IX, resistor |
| Heat Range | 6 (NGK) |
| Thread Size | M14 x 1.25 |
| Reach (thread length) | 19 mm |
| Hex Size | 16 mm |
| Seat Type | Gasket |
| Projected Tip | Yes |
| Centre Electrode | Fine-wire iridium (approx. 0.6 mm) |
| Ground Electrode | Nickel alloy, tapered cut |
| Terminal | Solid terminal |
| Factory Gap | 1.1 mm (-11 designation) |
| Gap Adjustability | Not recommended on iridium fine-wire tips |
Fitting notes
– Install into a cool engine. Hand-tighten first to avoid cross-threading, then tighten to the manufacturer’s torque specification.
– Use only the specified heat range and reach for your engine.
The price displayed is for a single plug, please add the desired amount to your basket.
| Weight | 0.05 kg |
|---|---|
| Dimensions | 10 × 3 × 3 cm |
| Brand |
NGK-6441 Confirmed Fitment
Our team haven't provided any fitment data for this product yet, please get in touch or check back later!
Stock at Progressive Parts
Delivery timescales are given as estimates in good faith, but cannot be taken as precise or exact information. We highly advise against booking installation/workshop time or engaging in preparatory work until you've received and inspected the goods.
What do our stock statuses mean?
1+ IN STOCK in green stock is readily available in one of our warehouses for express delivery (at the time of viewing).
LOW STOCK in green means we're running low! 1 or 2 left on the shelf so act fast. Over evenings, weekends and bank holidays this stock can move quickly so please bear this in mind.
0 IN STOCK in blue means our primary warehouse does not have unallocated stock, but our UK partners do. Often these can be shipped quickly and efficiently. You'll be notified via the Track My Order page if further delays are unavoidable.
MADE TO ORDER in blue means we've partnered with a supplier which primarily makes their products to order. It's not on our shelf, but your order goes into production immediately.
0 IN STOCK in orange means everybody we work with is unfortunately out of stock. Stock is not available in the UK. The best course of action is to place an order to create an allocation from the next batch arriving.
OUT OF STOCK in red. This product is unavailable to order, for whatever reason we're unable to obtain stock or there is an issue with supply/lead times.
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In some instances, extended lead times are unavoidable. This is as labour-intensive and frustrating for us as it is for you, please know we are doing our best to facilitate your modification goals. Abuse of our staff or systems will not be tolerated.
Thank you, Team PP
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For emissions components this encompasses noise, emissions and balanced back pressure, which have a strong influence on maintaining engine performance (power), and fuel efficiency. Type approval ensures that an aftermarket component will reach, or exceed the performance standard of the corresponding OE part.
Type-approval then, is a certain guarantee that an end user will receive a product of OE equivalent performance attributes.
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