Engine Gallery
What is my Marinization
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Pleasurecraft Marine (PCM) Ford 1986
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Commander 351
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1985 Commander 351 FWC
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Escort 302
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Indmar Ford
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1994 PCM 351 PTI
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PCM GT40 MPI Bobtail
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Indmar GM Carbureted
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PCM 454
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1995 Indmar LT1
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Indmar 454
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1996 Indmar Monsoon I
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2000 Indmar LTR
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2004 Marine Power 335
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2006 Indmar MCX
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Mercruiser Mag MPI
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351 Ford High Output (H.O.) Cylinder Head
Indicated by 3 raised ribs on the end of the head.
2 raised ribs indicates a standard 351, 250HP with hardened exhaust seats.
A flat head, with no raised ribs, indicates a older style without hardened seats, requiring Valve Tech or a lead substitute.
Flat Head and 2-rib heads are compatible, just make sure both take 14mm plugs.