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Authenticity reference

Cobra Jet block casting marker

numbers matching · reported

Reference Details

Common issue
Standard 428, 390, 410, or other FE block represented as a factory 428 Cobra Jet block.
Confidence
reported
Correct value
A typical Cobra Jet FE block has a sand-cast C on the rear of the block; an A rear mark indicates a standard 428 passenger-car block and no mark points away from a 428 CJ block in the cited detailing reference.
Where to check
Rear of the engine block; normally requires engine-out or difficult installed-engine inspection.

Cars With This Authenticity Marker

1 linked car page.

Sources & Documentation