Head part numbers

[ccryan67]

I began pulling the heads off of my 1957 FL this evening. The casting numbers on my heads are 16704-55 and 16706-55. So they're wrong for my year but I don't care. Palmer’s shows 1955 as having one year only heads 16704-55 and 16705-55. Anyone know the story behind the 16706-55 casting? CR

[john HD]

they probably are the correct ones as HD used the same molds for years. heads from the 60's used the same number on the casting even though the fins are much larger and have outside oilers.

you need to find the actual casting date code, it looks like a small tab with 2 numbers like 2-7 ie, feb 1957. also don't be suprized if you find they were actually cast in 1956.

john

[ccryan67]

You were right. The date tabs are 5-6 and 1-6. Even though Palmer's shows 56-57 as having part nos 16700-56 and 16701-56, that must not always be the case.

[VPH-D]

Early model year machines are likely to be equipped with lefover parts from the prior year. Some years are known to have "early year' models, 51, 73, and 78 are some common ones.

Also keep in mind that during the Panhead years, production dropped off almost every year, creating more leftover parts.
VPH-D