Is there much difference between a '50 Dodge head & '57 Plym head?

[BobT-47P15]

Hi guys.   

 

Am thinking it may be time to have the flathead six in the convert overhauled as it is putting out

white-ish smoke from the oil fill and road draft tubes.  Runs good aside from that.  Burns/leaks

a little oil along the way.

 

The engine block in the car now is supposed to be a 1957 Plymouth item, bored .030 over.

Would have been a 230 c.i. to start with.  May have 30 or so thousand miles on it since 

first rebuild.

When the mechanic installed this engine maybe 15 years ago.......he felt that the head on

my 1950 Dodge engine was in better condition than the head that came with the '57 motor.

So, I have a 57 Plym engine with a '50 Dodge head.  (Wasn't the Dodge a 230 also?)

 

Has always seemed to run just fine.

 

So.......I guess the question is --- does it matter which head is on that '57 block?

 

Head currently on the motor has a "D"  embossed on the top.  An apparent part number

of 1311804-2 and came from an engine marked D34-776I9 with a block casting date of

6-26-1950.

 

The presumed '57 head contains the number 1676337-2, the engine it came from is

dated 6-14-6, which I presume is June of 1956 and the .....engine number is

P30-85983.

 

Any thoughts or info would be helpful......thanks.  

Edited July 21, 2014 by BobT-47P15

[greg g]

If we are to assume that both heads are stock, the 50 Dodge engine had a CR of 7 to 1 the 57 Plymouth (and Dodge) had a Cr of 8 to 1.  Which would indicate to me that the 57 head has a smaller combustion area in order to achieve the higher CR.  The 50 engine Dodge engine was 103 HP.  the engines were rated at 132 HP for the Plymouth and 138 for the Dodge.  the Plymouth reading was at 3600 rpm and the Dodge at 4000.  So the 6 hp could be the result of an inter-mural pi$$ing match between brands.  but for me I would go with the head that made the most HP.

Edited July 21, 2014 by greg g

[Plymouthy Adams]

again however...only by CC'ing the head on either do you know the true size of the head combustion chamber and arrive at the correct CR value..to accept these older cars as being stock after all these years and previous owners, maintenance that may well have required truing of a head...is a value I would not leave to guessing...

[_shel_ny]

Internal/external bypass

[Tim Keith]

again however...only by CC'ing the head on either do you know the true size of the head combustion chamber and arrive at the correct CR value..to accept these older cars as being stock after all these years and previous owners, maintenance that may well have required truing of a head...is a value I would not leave to guessing...

 

I would like to have '57 heads for the 8:1 cr.  But I think milling the heads is about the same

[BobT-47P15]

Internal/external bypass

Yeah.....that's another thing I.m not sure about.  Have the neck with the short piece of hose....which is bypass as I recall.

Don't know if there is a thermostat or not.

 

And......will I need a new water distribution tube?

[_shel_ny]

And......will I need a new water distribution tube?

 

You won't know until you get in there

[_shel_ny]

Yeah.....that's another thing I.m not sure about.  Have the neck with the short piece of hose....which is bypass as I recall.

Don't know if there is a thermostat or not.

I believe you have made a post on this before- - - -the internal/ external. The 50 head is probably external bypass (no bump on the front). 57 block internal bypass. 50 head covers the internal bypass hole in the 57 block, so you are external bypass with the hose to the elbow atop the water pump. My understanding is that you need to have a bypass. Does not seem to matter which, as long as you have one. At least one member has both, and has no problem.