1957 Cadillac 365 Valvetrain Question

dqcad57365

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What vehicle(s) do you drive?
1951 mercury
I have a 1957 365 engine that I'm rebuilding, I got it off a neighbor who knew nothing about it, just wanted it gone. After tearing it down I've come to find out that at some point it dropped both valves on cylinder 3 and broke the no. 3 rod in two places. I'm currently have the block machined. My question is concerning the valvetrain on these engines. I've found out that there is two different push rod lengths (early/late production motors). During tear down it appears I have a early motor with late (shorter) push rods. Does anyone know if there are any other differences in the valve train? Lifters, Rocker Arms differences between early/late motor? I'm at a standstill on ordering motor parts until I figure out the valve train. We all know that the parts for these motors are expensive and i just don't want to ruin it by doing something stupid. Any info on valve train would be greatly appreciated.
 

Caddylackn

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That is news to me on the different push rod lengths. At some point in the early motors they changed the stroke between the 331 motors to the 365 then again for the 390. I thought the rocker hardware was the same from 50-66 as well as the deck height. Get yourself the factory Cadillac manual of your year. It will have all the specs you need you can compare to other years. You can find the originals factree manuals on Ebay or they make repros and you can even buy a CD of the factory manual.

Is this going in a '57 caddy or in a rat rod?
 

dqcad57365

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What vehicle(s) do you drive?
1951 mercury
That is news to me on the different push rod lengths. At some point in the early motors they changed the stroke between the 331 motors to the 365 then again for the 390. I thought the rocker hardware was the same from 50-66 as well as the deck height. Get yourself the factory Cadillac manual of your year. It will have all the specs you need you can compare to other years. You can find the originals factree manuals on Ebay or they make repros and you can even buy a CD of the factory manual.

Is this going in a '57 caddy or in a rat rod?
putting motor in my 51 merc. there is a difference in the pushrod lengths early/late for 57 engine, i'm still checking to see if the lifters are different too. from my motor the pushrods measure 9 9/16" and the lifters are 3/4" dia. by 2" long. the early pushrods measure 9 3/4" but i haven't found anything on the lifters yet. my motor has an early serial number (about 1000 before becoming late) but has the late pushrods (?) i'm just trying to get the correct parts without ruining my machine work. i know i can tell that much difference in fitment during reassembly, just dont want the hassle of shipping returns and delays
 
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