I've searched the archives for days, and there's plenty of interchange info about the Chrysler, but nothing about the little Dodge double rocker shaft Super Red Ram ? I was always told for a small inch hemi the Desoto would out flow them, so no aftermarket speed parts, but are the bore centers the same as anything else where the heads can be bolted on ? What about bellhousing pattern ? Not to confuse matters, but how about interchange among Dodge and Desoto? Where is this stuff written? Tom S. in Tn.
Chrysler Desoto and Dodge each had there own design. Heads for each motor were different . They will not interchange between motors. The bellhousing pattern is the same though
If you're asking if there is interchange between the 241 and 270 yes there is. They are both low deck Dodge hemis and most parts will interchange.. with the exception of pistons. Also there are a lot of performance parts available including new 4 bbl., dual 2bbl., and tri-power intakes. Hotheads has a load of stuff for the low and high deck Dodge hemis so don't sell them short. There aren't a lot of parts that will interchange between the low decks and high deck Dodges and pretty much nothing (with a couple minor exceptions) will interchange between Dodge, DeSoto and Chryslers.
You can obtain a book from Hot Hemiheads that is the 'bible' of early mopar hemi parts. It contains a wealth of information on part numbers, casting/forging numbers, dimensions, ID codes etc, etc. and is well worth the modest price. There are other sources of info about these engines, but for my money, this is the place to start. Ray
Interchanges, supposed to work: 55-58 Chr timing covers will fit Dodges, high deck Dodge & Desoto rods interchange.
I thought all the bellhousing patterns were the same? And also that the 241/270 heads will bolt onto a 270 Poly using the poly intake and different pistons and also the heads will go on a 315/325 Poly block using the tall deck Poly intake but that they don't flow well on the bigger motors. Is that all true?
bells are the same. Poly & hemi intakes interchange on Dodge, & on Chryslers, Plym & DeSoto Polys are Dodge blocks. Dodge heads interchange between high & low deck blocks. sealing @ the top of the head is marginal when using 241 heads on the high block.
OK, now I'm really confused. Sadly, I think those books concentrate on the Chrysler. 'I can't see why in the cat hair a corporation like DDCP would make a different motor for every car they ever made' I had 2 sets of mid 50's Dodge Super Red Ram heads and a marginal block and crank. I was wondering what hemi combo I might be able to whip up using later and/or more obtainable short block that might have the same bore centers. Are bore centers anything like a 318 knobby, or even a LA perhaps? Aren't the bells close to them ? Would the old 276D8 Hilborn made for the Desoto fit the little Dodge head? Thanx to all; Tom S.
You are not going to find another block to fit the heads. There are some other considerations such as the oil supply to the rockers,pushrod angle, deck heigth, bolt hole locatin, etc. You should be able to find another short block. A poly block would be the same. They made 259 and 270 poly's. It may be possible to fit the DeSoto injectors to the Dodge heads by redrilling the flanges. Some intake casings were designed with extra material for alternata machining. They run into problems because of the deck heigth so it is hard to switch after machining. The injectors are like log manifolds so the deck heigth is not a problem.
No, the DeSoto Hilborn setup would not fit on the Dodge heads, it'll only fit Desoto 276/291 engines, but if you have one it's gotta be super valuable. The only poly blocks that your Red Ram heads will fit on are 270 and 315/325, plus one version of the 270 that Plymouth used (not sure if it was 270 inch or 259, something like that). Not even close to fitting on a 318 of any vintage.
No different than Government Motors in the '50's.... Dodge heads fit on Dodge blocks...241-260-270-315-325 this includes the 57 DeSoto KDS which is a 325 Dodge Poly. DeSoto Hemi heads fit DeSoto Hemi blocks. More info in here: .
Dodge and Desoto rods will not interchange. The big end width of the Dodge is .901. The Desotos are .931
Thanx to all. I had those parts for years and finally parted with them for nearly nothing to a Red Ram collector, because I could not figure a practical use for them and I knew these guys could. I understood the Chrysler interchange and have used many of those combos, but had been confused thinking the little hemi compatibility was similar. This lays to rest all the lingering questions. Tom S. in Tn.
Sadly, there are plenty of errors in the book. It was most unfortunate that the contributors did not have any opportunity to proof read the copy before it went to print. .
A point of interest....All early Hemis use the same timing chain and gears, which can be replaced with an LA roller set.
No, not so fast... The 'early', long nose jobs are obviously different and caution must be used when installing the A-LA set on the others if you plan on using a mech fuel pump because of the woodruff key location. Not all keys extend forward of the sprocket and then you have nothing to engage the eccentric. .
I'm aware of a number of them. They have an insert correction for 1 error, but Ceridono was unaware of the others, as of a # of years ago.
I can't speak for the others but Ron was made aware of 'some' as soon as copies were send to the contributors.... I remember being told that a second printing was unlikely so there would be no opportunity to make corrections. .
........ or a gear drive ?? George states the Chrysler front cover works on these too. I always 'thought' the Desoto had it's own front cover like it's own injector manifold. Where can accurate information like bore centers be obtained ? Tom S. in Tn.
The only thing he'll aknowledge is the error in deck height that has a paper insert correction. This was years after the book came out.
Where the cam to crank distance is the same, anything for the LA will be spaced right, however, the low deck Dodges had long snout cams, you have to have that modified to work with the LA set, or find a high deck cam blank & have ground for use in a low deck.
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