AC 46 Spark Plugs
Posted: Mon May 11, 2026 11:24 pm
Found these old things (x4) rolling around in the bottom draw ... AC Delco 46 Spark Plugs
They look to be in good condition.
Wiki tells me .....
"The AC 46 is a classic 14mm thread, 3/8" reach, gasket-seat spark plug with a 13/16" hex, commonly used in older GM engines"
Buick: Various models (1938–1942, 1950–1952, and 1953 40 series) often used the 46X or 46.Oldsmobile: All 8-cylinder models from 1950-1954 used AC 46X.Chevrolet: 1960-1966 Chevy trucks and various 1960s-90s V8 models often used the R46N or R46S.Corvette: Used in classic V8 Corvettes, including 1965 Fuel Injection models.Pontiac: Used in 1932-1933 models.Other: 1951-1953 Packard "Junior" models using Delco ignition.
These "green stripe" plugs are pretty old school and may help someone doing a historic/concourse resto .....
"AC "Fire Ring" spark plugs are vintage, often green-ringed, NOS (New Old Stock) or reproduction plugs typically used in older GM vehicles and classic cars, notably in the AC 44 or 42FS series. These are not a modern high-performance technology, but rather a classic, reliable spark plug design often sought after for authenticity in restoration projects".
Free to anyone or their mate who could use them ..... let me know.
- IMG_5794.JPG (3.27 MiB) Viewed 390 times
- IMG_5795.JPG (2.63 MiB) Viewed 390 times
- IMG_5796.JPG (3.99 MiB) Viewed 390 times
Wiki tells me .....
"The AC 46 is a classic 14mm thread, 3/8" reach, gasket-seat spark plug with a 13/16" hex, commonly used in older GM engines"
Buick: Various models (1938–1942, 1950–1952, and 1953 40 series) often used the 46X or 46.Oldsmobile: All 8-cylinder models from 1950-1954 used AC 46X.Chevrolet: 1960-1966 Chevy trucks and various 1960s-90s V8 models often used the R46N or R46S.Corvette: Used in classic V8 Corvettes, including 1965 Fuel Injection models.Pontiac: Used in 1932-1933 models.Other: 1951-1953 Packard "Junior" models using Delco ignition.
These "green stripe" plugs are pretty old school and may help someone doing a historic/concourse resto .....
"AC "Fire Ring" spark plugs are vintage, often green-ringed, NOS (New Old Stock) or reproduction plugs typically used in older GM vehicles and classic cars, notably in the AC 44 or 42FS series. These are not a modern high-performance technology, but rather a classic, reliable spark plug design often sought after for authenticity in restoration projects".
Free to anyone or their mate who could use them ..... let me know.