The HKS Super Fire Racing M40HL is an HL-type iridium spark plug with an NGK 8 equivalent heat range (stock heat) for the Nissan/Infiniti VQ35HR 3.5L engine. The M12 long-reach, 14 mm hex design suits the VQ35HR, and the 0.6 mm iridium center electrode with platinum-chip outer electrode provides strong ignition and long service life while resisting carbon fouling. A direct performance upgrade at the factory heat range. Sold individually.
| Product Line | Super Fire Racing M-Series |
| Heat Range | NGK 8 equivalent (stock heat) |
| Seat / Type | HL type (M12 long reach) |
| Thread | φ12 x 26.5 mm |
| Hex (Wrench) | 14 mm |
| Center Electrode | 0.6 mm iridium |
| Application | Nissan / Infiniti VQ35HR 3.5L |
| Quantity | Single plug |
| Part Number | 50003-M40HL-1 |
Shipping: In-stock orders placed before 3 PM EST ship the same day, and everything else ships within 24 hours. Standard, expedited, and overnight options are available at checkout. Backordered items ship as soon as we get them back in stock. Contact us for lead times. See the full Shipping Policy.
Returns: 30-day returns on new, unused items in original packaging. See the full Refund Policy.
