Mystery Cylinder Head

[Pete]

Hi all,

I'm hoping someone can identify this cylinder head. The number on the head appears to be either 131804-3 or 131:804-3 or 1311804-3. See attached pics.

 

The block is original to my '39 Plymouth. The engine was worked on probably in the early 1950s based on dates stamped on replacement parts. It was bored out to 2 1/4 inches which makes it as 218 rather than the original 201.

 

The engine is currently being rebuilt. This head has been machined as part of the rebuild. It now has a compression ratio of about 7.5 to 1, which will still leave good flow. The top had .005 taken off to even things up. It is an external bypass head.

 

I have a number of Mopar parts books but can't find this part number anywhere.

 

Questions:

 

What does the big "D" on the head stand for? Dodge?

 

What is the extra tapped hole between #4 and #5 spark plugs for? It's the one with the bolt in it in the pics. It goes through to the combustion chamber. In the past it was plugged with a bolt and had nothing attached to it. It has a boss which makes it look line part of the original casting. This is not the timing hole over the #6 cylinder.

 

Mostly, what engine and vehicle did this head originally come on? What years was it used?

 

Also, I got an NOS cylinder head that is correct for 201 & 218 heads. My engine builder cc'ed it and said he can't take enough off to get the CR anywhere near the current head, so it was decided to use the mystery head and not use the NOS head.

 

Thanks,

Pete

 

Edited December 30, 2019 by Pete
Corrected typo.

[Young Ed]

The 50s cars have a stud in that random hole for the throttle linkage to pivot on. 

[NickPickToo]

Beautiful 

[dpollo]

the unused hole is for the  throttle bell crank on post war  engines and it cannot go through to the combustion chamber as it would interfere with the gasket. It does go into the water jacket.   Plymouth heads of this era had a P  where yours has a D  I think it is safe to assume D is for Dodge.

[Plymouthy Adams]

I think these letters are for the foundries of the time....not so much make of vehicle....per a post I read somewhere long ago on a forum maybe not this one....

[Sniper]

Went and looked at my 51 Plymouth's head, It has a big P on it, so the D may very well mean Dodge.  Casting number is not the same either.

[Plymouthy Adams]

and NH is what.…?

[chrysler1941]

14 hours ago, Plymouthy Adams said:

and NH is what.…?

Yes was does it mean. My head is an older model and has no P or D stamping only NH.

From Wikipedia

 

 

 

Indianapolis Foundry was a Chrysler automobile foundry located at 1100 S. Tibbs Avenue in Indianapolis, Indiana. The factory opened in 1890 as the "American Foundry Company" and was purchased in 1925 by Chrysler and operated as a subsidiary. It became part of Chrysler property in 1946 and expanded in 1964, 1978, 1988, and went through a major remodel from 1996 through 2000. The plant covered 52 acres (210,000 m²) on Indianapolis' west side.^[1]

 

Edited December 31, 2019 by chrysler1941

[chrysler1941]

They also had

 Chrysler Corp Huber Ave Foundry. Chrysler Corp Huber Ave Foundry , 6425 Huber Ave, Detroit MI, 48288.

H for Huber ?

[Plymouthy Adams]

if I recall correct, someone in the past on another Mopar forum stated it was North Hamtramck...but then again....this was just something I read.....Huber was not in play at this time

[dpollo]

On 12/30/2019 at 5:26 PM, Plymouthy Adams said:

and NH is what.…?

Our old forum friend Nuckle Harley ?  no that would be KH     .   haven't seen any action from him on the forum lately. hope he is OK.

[Plymouthy Adams]

We have a few MIA's here, he disappeared once before, I made an inquiry and he surfaced. this time is has exceeded 4 months since his visit.....I have no way to contact him other than open forum.....you do wonder as to how they are doing....

[dpollo]

always curious.  I would have had his email address except i had my computer serviced by a local genius who lost all my contacts. I recollect it was sneakypete @ ?? I will see if I have it written down somewhere.

[greg g]

knuckleharley last visited in August 2019 according to the last activity shown on his profile page in the alpha members list.