Bohnalite Cylinderhead

[moparswede]

Hi, I found a bohnalite cyl head for short flathead mopar, does someone know anything about this head. was it aftermarket or Mopar OEM.

Regards Roger

[greg g]

Most likely aftermarket.  A picture or two might be helpful.  And Google can be your friend;

http://theoldmotor.com/?p=67095

Edited March 9, 2013 by greg g

[mayflower48]

greg g,  Thanks for the link. Great information on the history of pistons.

[moparswede]

on the google I mostly find info about pistons and ford heads not anything about mopar heads. I will try later to post some pics I must shrink them first.

I found some info about a "Red Head" option that mopar offered to there cusomers in early 30:s, can it be the head I found?

Edited March 9, 2013 by moparswede

[greg g]

I  believe red heads were only produced in 31,32 for 4 cylinder engines.

[moparswede]

I found in my partbook that MOPAR had a option head with partnr 671178. It says it has higher comp and was made of alu. must be that type that i found.

[Alshere59]

How about posting a picture?  Or two.

[moparswede]

[moparswede]

Edited March 10, 2013 by moparswede

[greg g]

Got any shots of the combustion chambers, looks like the plugs are centered as opposed to the stock position.  Probably around 8 to 1 CR depending on the engine it's mounted on.

[Alshere59]

This web site shows the Red head for a 6 cylinder in 1933 but it is 189 cubic inch. What year does the part number you listed show? Also anyone know if a 189 cubic inch fits a 218/230 if that is what we are looking at? Very cool regardless. I like it. 

http://www.allpar.com/mopar/flat.html

[moparswede]

in my partbook it says it fits p1 to p8 and pt50,pt57, pt81  my book ends in 39 so I dont know if it fits later models, I will send more pics tomorrow on the combustion cambers //Roger

Edited March 10, 2013 by moparswede

[Alshere59]

Well I probably over thought this but I was curious. Looks like the head gaskest for this and an external bypass head, say 218 are the same up to 1949. So if it was used on a 230 would the compression be higher? This assumes it is a red head. Which sounds right anyway.

 

Al

[TodFitch]

This web site shows the Red head for a 6 cylinder in 1933 but it is 189 cubic inch. What year does the part number you listed show? Also anyone know if a 189 cubic inch fits a 218/230 if that is what we are looking at? Very cool regardless. I like it. 

http://www.allpar.com/mopar/flat.html

 

The '33 189.8 (190) cu. in. engine and the '34 201 engine do not have the full length water jacket and the block is not as wide as the '35 and up engines. So the head and head gasket for '33/34 are different than all the later Plymouth L-6 engines.

 

1933 - 189.8 cu.in. First year for the L-6 on Plymouth a number of running changes, especially in the oil pump and oil pressure relief system, so check your engine number carefully!

1934 - 201 cu. in. Basically a stroked late '33 engine. Shares same main and connecting rod bearings and pistons but uses different crank and rods.

1935-41 - 201 cu. in. Same crank, bearings, rods pistons as '34 but wider block to accomodate water distribution tube and full length water jackets.

[Alshere59]

Thanks Todd my books do not go back that far. So moparswedes part number fits P1 and a P8, so 1936 to 38 which would have had the full water jackets. Checking for a head gasket at Bernbaums shows a part number of L-131 fitting a 1935 (201) to the 1948 Plymouth which had a 218 engine. So it should fit a later engine. I would think that the compression ratio would be low but that is a guess. It would look sweet polished and sitting on the engine though.

 

From here I got the below for specs: http://olskoolrodz.com/forum/showthread.php?t=18165

US made small bores:
3.125X4.375 201cid Plymouth 35-41
3.250X4.375 217cid DodgePlymouth 41-54
3.250x4.625 230cid DodgePlymouth 54-59