Help! Identify these heads!

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Jun 5, 2015 | 01:12 PM

Resurrected 56 F100

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From: Somewhere in the desert

Help! Identify these heads!

There are no casting numbers on my heads as the numerous websites have shown. I've only found "73B", a "G" and a "15". The valves are the larger 1.92" size. Are these the ECZ-G heads?

Jun 5, 2015 | 04:02 PM

charliemccraney

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The numbers will be on the heads somewhere. Make sure it is clean, use a light, and magnifying glass, if necessary.

I'm pretty sure that is a G head.

Jun 5, 2015 | 04:23 PM

Resurrected 56 F100

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From: Somewhere in the desert

I guess its time to pull out the 'ole drill and wire brush.

Jun 5, 2015 | 10:55 PM

hiball3985

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From: tujunga, calif

It looks like a G head. The casting numbers are usually on the intake port side of the head at one end..

Jun 12, 2015 | 10:54 AM

Resurrected 56 F100

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From: Somewhere in the desert

I found the casting number! It's ECZ-G. Aren't these fairly desirable heads? I like the fact that they have the bigger valves. Now I wish I knew if these were '57 or '58...

Jun 12, 2015 | 11:18 AM

charliemccraney

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They are among the best factory heads for the Y.

I'm rusty on date codes, but I think the 73 and backwards B is the date code, so 1957 (7) March (3) 26 (backwards B). The letter corresponds to the day of the month, excluding I and O for confusion, that's 24 days and the backwards letter indicates that the count started over, so 24 + 2 (B) is 26.

The date doesn't matter much, unless you are trying to build a vehicle to be as correct as possible and these are not correct if they are for a 56 F100.

Jun 12, 2015 | 01:33 PM

Resurrected 56 F100

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From: Somewhere in the desert

Nice! No, not trying to be correct, just trying to find the most accurate specs for this engine. Thanks for explaining the 73 B.

My dad and grandpa actually swapped this engine in to replace the 272 back in '69 or '70.