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Authenticity reference

Early 405-hp cylinder heads

numbers matching · documented

Reference Details

Common issue
Later Super Duty heads or common Pontiac heads may be substituted during racing or restoration.
Confidence
documented
Correct value
540306 heads with 1.92-inch intake and 1.66-inch exhaust valves where the claimed early configuration calls for them
Where to check
Cylinder-head casting numbers, valve dimensions, dates, and supporting parts or installation records

Cars With This Authenticity Marker

1 linked car page.

Sources & Documentation