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MSD Iridium Spark Plug 3720

MSD Iridium Spark Plug 3720
$14.99 ea
NEWOUT OF STOCK
Model: 4017178
Select a Vehicle or refer to the Vehicle Fitment Tab below to verify that this part fits your vehicle.
STANDARD
DELIVERY
MSD's spark plugs are engineered to improve the efficiency of the combustion process to create the most power possible combined with increased durability. The center tip of the plug is made from iridium to promote the best spark and increase resilience. A proprietary ceramic material enhances the dielectric strength of the plug housing forcing the spark, even under extreme cylinder pressures, to jump across the plug gap to the ground electrode. This electrode is machined to expose more spark to the incoming gases to promote the most effective combustion event possible.
Features:
  • Proprietary plug design inside and out
  • Designed for use on high performance vehicles that utilize high output ignition systems
  • Machined electrode increases exposure to the flame to improve combustion
  • MSD’s proprietary ceramic formula provides the highest dielectric strength
  • Yttrium ground electrode reduces the chance of pre-ignition
  • Iridium tip improves cold starts
  • All spark plugs tested prior to packaging and shipping
  • Unique insulator design improves spark isolation
  • Lower voltage Requirements for longer coil life
About MSD Ignition

Racers never stop experimenting as they search for every way to wring out more power or handling performance to to gain an edge over the competition. The team at MSD is no different as we strive to deliver the products you  need to meet your performance goals. We continue to innovate and invent components and technology that deliver  performance and reliability with products that are easy to use and install. 

Over the course of 40-plus years, MSD Performance has been driving the development of innovative components  that helped shape the way our cars race and perform. From super speedways to road courses, land speed racing to  top fuel dragsters, and of course your traditional hot rod, MSD has provided the components to fire nearly anything in  motorsports.

MSD was the first company to develop and offer the multiple sparking, capacitive discharge ignition for engines. The line of MSD 6-Series Ignitions are the most popular aftermarket ignitions in the world due to our race-proven performance on the track and our reliability on the street!

Early on, MSD focused squarely on ignition systems with revolutionary products like the multiple sparking CD ignition, timing and rev controls, billet aluminum distributors and the Pro-Mag, an incredible breakthrough in power  and endurance. 

Today MSD is developing electronics for your entire powertrain. The Atomic EFI systems for the LS engine platform and throttle body are now complemented with a transmission controller. Our DynaForce Starters and Alternators  ensure that your engine cranks over to fire up and the Alternators keep it charged. MSD is poised to deliver components that work and communicate together to provide performance and value.

Videos:

Vehicle Fitment:

The Vehicle Fitment Guide is to be used as a general reference. The data has been provided by our suppliers and manufacturers and may contain errors or incorrect data. Always refer to a professional to verify correct fitment for your vehicle.
Make Model Submodel Years Engine Fitment Notes
Ford Mustang II Base 1975 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang II Base 1976 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang II Base 1977 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang II Ghia 1975 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang II Ghia 1976 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang II Ghia 1977 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang II 1975 5.0L / 302 / V8
Ford Mustang II 1976 5.0L / 302 / V8
Ford Mustang II 1977 5.0L / 302 / V8
Ford Mustang Base 1969 5.0L / 302 / V8
7.0L / 429 / V8
7.0L / 428 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Base 1970 5.0L / 302 / V8
7.0L / 429 / V8
7.0L / 428 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Base 1971 5.0L / 302 / V8
7.0L / 429 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Base 1972 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Base 1973 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Base 1979 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Boss 302 1969 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Boss 302 1970 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Boss 302 1971 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Boss 429 1969 7.0L / 429 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Boss 429 1970 7.0L / 429 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GLX 1982 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GL 1982 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT-350 20th Anniversary 1984 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GTS 1995 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1982 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1984 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1985 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1986 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1987 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1988 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1989 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1991 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1992 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1993 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1994 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang GT 1995 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Ghia 1979 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Grande 1970 5.0L / 302 / V8
7.0L / 429 / V8
7.0L / 428 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Grande 1971 5.0L / 302 / V8
7.0L / 429 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Grande 1972 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Grande 1973 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang LX 1984 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang LX 1985 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang LX 1986 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang LX 1987 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang LX 1988 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang LX 1989 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang LX 1991 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang LX 1992 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang LX 1993 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang L 1982 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang L 1984 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang SVT Cobra R 1993 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang SVT Cobra 1993 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang SVT Cobra 1994 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang SVT Cobra 1995 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Shelby GT-500 1969 7.0L / 428 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang Shelby GT-500 1970 7.0L / 428 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang 1969 5.0L / 302 / V8
7.0L / 429 / V8
5.8L / 351 / V8
7.0L / 428 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang 1970 5.0L / 302 / V8
7.0L / 429 / V8
5.8L / 351 / V8
7.0L / 428 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang 1971 5.0L / 302 / V8
7.0L / 429 / V8
5.8L / 351 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang 1972 5.0L / 302 / V8
5.8L / 351 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang 1973 5.0L / 302 / V8
5.8L / 351 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang 1979 5.0L / 302 / V8
Ford Mustang 1980 4.2L / 255 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang 1981 4.2L / 255 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang 1982 5.0L / 302 / V8
4.2L / 255 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Ford Mustang 1984 5.0L / 302 / V8
Ford Mustang 1985 5.0L / 302 / V8
Ford Mustang 1986 5.0L / 302 / V8
Ford Mustang 1987 5.0L / 302 / V8
Ford Mustang 1988 5.0L / 302 / V8
Ford Mustang 1989 5.0L / 302 / V8
Ford Mustang 1991 5.0L / 302 / V8
Ford Mustang 1992 5.0L / 302 / V8
Ford Mustang 1993 5.0L / 302 / V8
Ford Mustang 1994 5.0L / 302 / V8
Ford Mustang 1995 5.0L / 302 / V8
Mercury Capri Base 1979 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Capri Ghia 1979 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Capri RS 1982 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Capri RS 1983 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Capri RS 1984 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Capri RS 1985 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Capri 1979 5.0L / 302 / V8
Mercury Capri 1980 4.2L / 255 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Capri 1981 4.2L / 255 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Capri 1982 5.0L / 302 / V8
4.2L / 255 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Capri 1983 5.0L / 302 / V8
Mercury Capri 1984 5.0L / 302 / V8
Mercury Capri 1985 5.0L / 302 / V8
Mercury Cougar Base 1969 7.0L / 428 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Base 1970 7.0L / 428 / V8
7.0L / 429 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Base 1971 7.0L / 429 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Base 1977 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Base 1978 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Base 1979 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Base 1983 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Base 1984 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Base 1985 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Boss 302 1970 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Boss 429 1969 7.0L / 429 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Boss 429 1970 7.0L / 429 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Brougham 1977 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Cobra Jet 1969 7.0L / 428 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar Cobra Jet 1970 7.0L / 428 / V8
7.0L / 429 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar LS 1983 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar LS 1984 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar LS 1985 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar LS 1991 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar LS 1992 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1969 7.0L / 428 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1970 7.0L / 428 / V8
7.0L / 429 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1971 7.0L / 429 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1977 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1978 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1979 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1980 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1981 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1991 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1992 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar XR-7 1993 5.0L / 302 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1969 7.0L / 428 / V8
7.0L / 429 / V8
5.8L / 351 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1970 7.0L / 428 / V8
7.0L / 429 / V8
5.0L / 302 / V8
5.8L / 351 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1971 7.0L / 429 / V8
5.8L / 351 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1972 5.8L / 351 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1973 6.6L / 400 / V8
5.8L / 351 / V8
7.5L / 460 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1974 6.6L / 400 / V8
5.8L / 351 / V8
7.5L / 460 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1975 6.6L / 400 / V8
5.8L / 351 / V8
7.5L / 460 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1976 6.6L / 400 / V8
5.8L / 351 / V8
7.5L / 460 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1977 6.6L / 400 / V8
5.0L / 302 / V8
5.8L / 351 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1978 6.6L / 400 / V8
5.0L / 302 / V8
5.8L / 351 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1979 5.0L / 302 / V8
5.8L / 351 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1980 5.0L / 302 / V8
4.2L / 255 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1981 5.0L / 302 / V8
4.2L / 255 / V8		 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1982 4.2L / 255 / V8 Iridium Tip Spark Plug; Single; Plug Type 6IR4Y; [Available While Supplies Last];0.035 in. Plug Gap;
Mercury Cougar 1983 5.0L / 302 / V8
Mercury Cougar 1984 5.0L / 302 / V8
Mercury Cougar 1985 5.0L / 302 / V8
Mercury Cougar 1991 5.0L / 302 / V8
Mercury Cougar 1992 5.0L / 302 / V8
Mercury Cougar 1993 5.0L / 302 / V8

Specifications:

Emission Code 2
Heat Range 4
Hex Size 5/8
Length Standard
Part Type Spark Plug
Plug Style Code 6IR4Y
Product Type Spark Plug
Projected Tip Yes
Proposition 65 www.P65Warnings.ca.gov
Quantity 1
Reach 0.4375
Resistor Yes
Seat Type Tapered
Style Iridium
Thread Size 14mm
Warranty Limited 1 Year Warranty

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