AC Spark Plug N5, 5612645

Description:

🔧 Part Overview

• ACDelco Part Number: N5

• GM Part Number: 5612645 (commonly associated with N5 in GM catalogs)

• Type: Non-resistor copper core spark plug

• Thread Size: 14mm x 1.25mm

• Seat Type: Gasket

• Reach: Approx. 19mm (0.75")

• Hex Size: 13/16"

• Terminal: Fixed

• Electrode Material: Copper core with nickel alloy ground electrode

• Country of Origin: Typically marked “Made in USA”

🚗 Specific Applications

The N5 plug was widely used in:

• 1950s–1970s GM vehicles including Chevrolet, Pontiac, Oldsmobile, Buick, and Cadillac

• Small-block and big-block V8 engines (283, 327, 350, 396, 427, 454 CI)

• Chevrolet Corvette, Camaro, Chevelle, Impala, Nova

• Marine engines (OMC, MerCruiser)

• Industrial and agricultural engines

• Classic hot rods and performance builds using 14mm gasketed heads