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HKS 50003-M40LF Iridium M-Series Super Fire Racing Spark Plug

(2006-2013 Mazda 3; 2005-2012 Mazda 6; 2006-2014 Mazda MX-5 Miata; 2007-2011 Mazda CX-7; 2012-2013 BMW 328i; 2009-2013 BMW Z4 sDrive35i + 3 more models)

Part of: HKS M-Series Super Fire Racing Iridium Spark Plug

Other options in this family: HKS 50003-M45iL HKS 50003-M45HL HKS 50003-M45XL HKS 50003-M50HL HKS 50003-M40XL

Manufacturer

Picture for manufacturer HKS

Part Number

50003-M40LF
8 reviews
Sale Price

$300.00

3 left at this price

delivery box

Usually delivered within 2 days

free shipping

FREE SHIPPING

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No Hassle Returns

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Live-in-stock inventory

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Fitment guaranteed

Fitment guaranteed

Product Details

The HKS 50003-M40LF is a high-performance M-Series Super Fire Racing spark plug featuring advanced iridium alloy construction for superior ignition performance, exceptional durability, and resistance to carbon buildup under demanding conditions.

Key Features:

  • 0.6mm iridium alloy center electrode for optimal spark concentration and longevity
  • Platinum-tipped outer electrode for extended service life
  • Short-type outer electrode design provides superior anti-vibration properties
  • Thermal edge technology ensures consistent heat dissipation
  • Spark support gap optimizes ignition efficiency
  • Ultra-high melting point of 2454°C withstands extreme combustion temperatures
  • Nickel-coated housing prevents premature deterioration

Engineered specifically for high-load applications, the M-Series spark plug delivers reliable ignition performance even under advanced tuning conditions. The iridium alloy electrode construction combines a narrow core diameter for concentrated spark energy with exceptional durability that resists wear from high compression and minor detonation. This design ensures consistent performance across extended service intervals while maintaining resistance to carbon fouling.

Note: Spark plugs are sold individually. Heat range and application-specific fitment should be verified for your vehicle.

Products specifications

Fits

2006-2013 Mazda 3; 2005-2012 Mazda 6; 2006-2014 Mazda MX-5 Miata; 2007-2011 Mazda CX-7; 2012-2013 BMW 328i; 2009-2013 BMW Z4 sDrive35i; 1967-1979 Buick Riviera S; 1968-1989 Buick Electra 225 Limited; 1965 Buick Sportwagon Base

Heat Range

8

They have the best prices and fast shipping too.

The shipping was fast and the customer service was great. I accidentally hit submit twice, and they promptly cancelled my accidental order. If you have any problems, just call!

Great price and fast shipping!

Best price I could find! Great customer service kept me informed through the whole order process to insure acuracy since it was being sent directly from the manufacture. Recieved my order in good time, right parts and no damage. Overall very satisfied and will be doing business again in the future.

Very competitive low prices and great product selection. Will definitely look to this vendor when purchasing automotive parts in the future.

Great prices and FAST shipping!! Definitely will buy products here again!

Fast like the Amazon buying method

Although there was a mix up with the shipping on my order customer service was helpful and expedited the solution and made it worth my trouble. I will be keeping Autoplicity in mind for any other parts I might need for my Jeep.

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