Lloyd Posted September 10, 2013 Report Share Posted September 10, 2013 Does anyone know what the letters on a flathead 6 cylinder head mean? Ive been looking at a head on the P15-D24 Store and there is an advertisement for 3 cylinder heads. It says One stamped with P and 2 stamped with D. Does the P or D stand for Plymouth and Dodge? Quote Link to comment Share on other sites More sharing options...
Robert Horne Posted September 10, 2013 Report Share Posted September 10, 2013 I have a 1956 Dodge engine that has the large P on the head. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted September 10, 2013 Report Share Posted September 10, 2013 P is Philadelphia D is Denver.... makes as much sense as anything else... Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted September 10, 2013 Report Share Posted September 10, 2013 My Dodge truck engine also has a "P" on the head. Not sure what it stands for. Quote Link to comment Share on other sites More sharing options...
greg g Posted September 10, 2013 Report Share Posted September 10, 2013 Conventional wisdom would suggest that Plymouth engines would have P's and Dodges a D, but this has not been documented where any one can point to it with any reliability. Hey Tim, don' t forget the "S" marked ones, I understand they are more scarce that the Phila, and Denver ones. It has been established that Blocks were cast and then allowed to sit in outdoor storage for as much a 2 years. Photo evidence shows them sitting on pallets out in the weather. I would imagine that heads were cast and stored separately till production demand move them to assembly areas. Quote Link to comment Share on other sites More sharing options...
Lloyd Posted September 10, 2013 Author Report Share Posted September 10, 2013 Well, thanks for the input. Guess it mostly means it don't mostly matter. One more question. I know the heads between a 218 and 230 can be swapped - bolt for bolt - if you swap them will it affect the compression ratio from one engine to another? Quote Link to comment Share on other sites More sharing options...
greg g Posted September 10, 2013 Report Share Posted September 10, 2013 There has been some discussion regarding certain head/ block combinations yielding higher compression, but I can not remember what was suggested. You could compare the heads by filling the head chamber with a liquid, then comparing the volume recovered from the heads. If one takes less to fill, it would suggest if would provide more squeeze. The later 218's had more compression than the early ones so likely their volume is likely smaller, but the same can be said for the 230. The 56 Dodge 230 had 7.6 to one, th 57 and newer were 8 to one. 218 highest was 7.25 to one, in 1954. Quote Link to comment Share on other sites More sharing options...
Lloyd Posted September 10, 2013 Author Report Share Posted September 10, 2013 Thanks Greg, I have an option to purchase a block - cleaned and fluxed, but then I have to get a head for it. Sounds like it would mostly be pot luck unless the castings on the head tell anything. I don't guess the difference between heads will be that noticeable without going the whole route, dual carbs, headers ... Which I am not doing. Having some problems finding a complete engine but found a couple blocks - so looking at building one piece by piece. Did a spreadsheet on it last night and came up with a little over $2000 to get all internal parts for a motor - and that pretty much just gives me a short block. DONG! It would certainly be a new motor but I felt a little dimmed when I saw that. Quote Link to comment Share on other sites More sharing options...
P15-D24 Posted September 10, 2013 Report Share Posted September 10, 2013 Later heads (post '53) typically have an a port for internal water pump bypass. (The bump on the front edge.) Earlier head are for external bypass setup. Quote Link to comment Share on other sites More sharing options...
ptwothree Posted September 10, 2013 Report Share Posted September 10, 2013 Anyone know of an easy way to I.D. a '56 and up cyl. head? I'd like to get one............ Quote Link to comment Share on other sites More sharing options...
Young Ed Posted September 10, 2013 Report Share Posted September 10, 2013 Dang wanna make a trip to MN? I could give you a 218 or 2...... Quote Link to comment Share on other sites More sharing options...
greg g Posted September 10, 2013 Report Share Posted September 10, 2013 (edited) I did my 56 230 engine 10 years ago, parts and machine work was and parts were in the 1700 dollar range back then. So not suprised its more 10 years later. have you checked with the folk a Terrill machine down there in TX. Good people decent prices. Edited September 11, 2013 by greg g Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted September 10, 2013 Report Share Posted September 10, 2013 (edited) Conventional wisdom would suggest that Plymouth engines would have P's and Dodges a D, but this has not been documented where any one can point to it with any reliability. Hey Tim, don' t forget the "S" marked ones, I understand they are more scarce that the Phila, and Denver ones. I was going to Post also: S =Sacramento CC= Carson City not everyone here has a sense of humor... Edited September 10, 2013 by Plymouthy Adams Quote Link to comment Share on other sites More sharing options...
TodFitch Posted September 10, 2013 Report Share Posted September 10, 2013 I was going to Post also: S =Sacramento CC= Carson City not everyone here has a sense of humor... I thought "S" was for San Francisco. Never heard that Sacramento had such a facility. . . Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted September 10, 2013 Report Share Posted September 10, 2013 (edited) never had enough money to know where it comes from..but I assure you that I can tell you where it goes....thanks for the correction Tod Edited September 10, 2013 by Plymouthy Adams Quote Link to comment Share on other sites More sharing options...
james curl Posted September 10, 2013 Report Share Posted September 10, 2013 I did my 218 in 2006 which included having the harmonic balancer rebuilt along with surfacing the flywheel and disc and rebuilding the pressure plate. I did not have to buy a new crank but did have to have it welded up in the thrust surface area and re-machined to factory dimensions plus turning all of the bearing journals. The cost of doing so was about as much as buying another crank so I did not save any there. I had all of the mating surfaces machined flat to provide a good sealing surface. Had the mains line bored and bored the block .040 over with new pistons,pins,and bushings. Had the rods re-manufactured, new guides and valves and had the cam reground for more lift and duration. I did all of the re assembly work and installed it in the car with all new rubber mounts. The car cost me $2500.00 when I bought it in 1986 and the engine rebuild and installed in the car cost in excess of $3000.00 in 2006. It become obvious I do not care about how I spend my money as long as the car remains powered with a flat head six. 1 Quote Link to comment Share on other sites More sharing options...
Dodgeb4ya Posted September 10, 2013 Report Share Posted September 10, 2013 Anyone know of an easy way to I.D. a '56 and up cyl. head? I'd like to get one............ By the part number. Quote Link to comment Share on other sites More sharing options...
Niel Hoback Posted September 10, 2013 Report Share Posted September 10, 2013 I have a "Bright Uncirculated" P head. Quote Link to comment Share on other sites More sharing options...
DLK Posted September 10, 2013 Report Share Posted September 10, 2013 I did my 56 330 engine 10 years ago, parts and machine work was in the 1700 dollar range back then. So not suprised its more 10 years later. have you checked with the folk a Terrill machine down there in TX. Good people decent prices. Maybe the $2400-2500 I am paying for parts and machine work in 2013 isn't so bad. At least I have a guy who has rebuilt many Mopar flatheads and had many satisfied customers like Young Ed. Quote Link to comment Share on other sites More sharing options...
Young Ed Posted September 11, 2013 Report Share Posted September 11, 2013 Maybe the $2400-2500 I am paying for parts and machine work in 2013 isn't so bad. At least I have a guy who has rebuilt many Mopar flatheads and had many satisfied customers like Young Ed. You are also getting assembly I believe which it sounds like James did himself. Yes he built both the flatheads in my 46 and 48 plus 2-3 for Dad. Quote Link to comment Share on other sites More sharing options...
Lloyd Posted September 11, 2013 Author Report Share Posted September 11, 2013 I did my 56 330 engine 10 years ago, parts and machine work was in the 1700 dollar range back then. So not suprised its more 10 years later. have you checked with the folk a Terrill machine down there in TX. Good people decent prices. No, but I will give them a call see what they got. Thanks for the link. Quote Link to comment Share on other sites More sharing options...
knuckleharley Posted September 11, 2013 Report Share Posted September 11, 2013 Did a spreadsheet on it last night and came up with a little over $2000 to get all internal parts for a motor - and that pretty much just gives me a short block. DONG!It would certainly be a new motor but I felt a little dimmed when I saw that. That's not bad. I spent a little over 1800 bucks to get a machine shop to rebuild the 194 cu in 6 in my 58 Rambler maybe 10 years ago,and that didn't even include new pistons because the bore was fine from a previous rebuild that ignored everything else. The engine even got new valve springs,valves,hardened seats,new cam,new tappets,turned crank,new timing chain,and a new oil pump. And the guy that owned the machine shop is a friend of mine that gave me a deal on the labor. 2 grand to completely rebuild a flat 6 on today's dollar is a pretty good price. Quote Link to comment Share on other sites More sharing options...
lheadandy Posted October 6, 2013 Report Share Posted October 6, 2013 Ive had 4 dodges from 46 to 51 all had D on the head. And one plymouth 55 with P on the head. When I was younger I bought a chrysler head with spitfire on it. I liked the word spitfire so I bought it to put on my 51 wayfarer. The car is gone, but Ive still got the chrysler head. That makes me a sht head. 1 Quote Link to comment Share on other sites More sharing options...
greg g Posted October 7, 2013 Report Share Posted October 7, 2013 Gotta have a 25 inch chrysler or desoto block for it. Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted October 7, 2013 Report Share Posted October 7, 2013 As Greg said, the Spitfire head is for long block Crashler and Desoto engines only. Will not fit on a Dodge or Plymouth engine unless they are a Canadian made engine. Quote Link to comment Share on other sites More sharing options...
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