I was talking to a buddy of mine this morning and he told me that he had picked up what he thought was an old 56 or 57 Chrysler that has a Polydine engine in it. Seems like I remember that they could be converted to hemi heads without too many problems. He said that the engine was running and the old car was solid, was asking $1,500.00 for it. Is that a reasonable price? What cubic inch would that engine be, 331, or 354? Any info would be appreciated. Thanks.
From 1955 to 58 Chrysler used 301-331 and 354 Poly head motors, not positive but don't think the 354 got in till 56 or 7. They are stout motors, never heard of putting Hemi heads on them but the Poly heads will draw as many interested onlookers wanting to know what the hell it is than a Hemi. I just sold a 66 Plymouth with the 318 Poly (last year it was ever used) and with a 4 speed and flowmasters it went and sounded great.
The Chrysler Polysphere engine was cheaper alternative to the Hemi. The Polysphere heads use one rocker shaft per head rather than two. Hemi heads will bolt onto a Polysphere because the block is basically the same. Note the spelling.
There's a site, http://www.1962to1965mopar.ornocar.com/poly318.html that gives soup up info... seem to be a pretty stout motor. My little bro had one someone gave him thinking it was a "regular" 318 when we were "kids". Wish I'da kept it. I'd be interested in engine pix if you go to look at it. Jay
The polysphere Aka poly was 331 in56 &354 in 57.Those built Through 58 were built on hemi blocks & can be converted by changing heads, pushrods, & pistons.$1500 seems steep considering the additional scrounging. TWJoice's comments have a good point, the polys were totally ignored because of its bro. the Hemi. You will almost be guarenteed to be the only one at an event, & all the 55 -58 intakes (mild to wild) will fit. The design is a canted valve simular to the Ford Clevelands
The Plymouth Polysphere engine is a differant animal. The Plymouth poly is the "A" series. It was transformed into the modern "LA" series (as in the 318-360) in the 1960's and later into the 360 magnum. I have done the research on this. Chrysler, Dodge, and Desoto Hemi heads will not bolt-on a Plymouth poly. The bore spacing, bolt holes, water p***ages, and everything else is different.
I found a site http://www.hothemiheads.com that has a lot of good info on them. Looks like a hemi rebuild kit runs about $1,400.00 plus labor for machine work. Probably another $6-800.00 for heads and valve work, plus about $300.00 for an intake. Trans adapters are around $400.00 this looks like it's adding up pretty fast. Found another one at a junkyard that the guy says is "mostly Comple" and will turn over. It's the old "I think I have it sold, guy is supposed to come by and give me a deposit on it today" He's wanting $1,500 for it, may go up and look at it and see if it's a 331 or a 392.
Chysler, Desoto, Dodge and Plymouth all had their own OHV V8 engine development programs. The Chrysler, Desoto and Dodge hemis were twinned with Polyspherical headed engines. Plymouth had no Hemi. There were additionaldisplacement engines for Canadian and other export markets. After 57 The Hemis were discontinued except for the Chrysler 300D and Imperial for 1958. After that no Hemi. The Poly engines continued through 58 and there may have been some in 59 The 361 B engine appeared in 58. The Chrysler 383 and the Desoto 383 both appeared in 59. These are separate designs with the same displacemnt with little in the way of parts interchange, The Chrysler design had some design faults and the Desoto 383 went on to become the venerable 383 that we all know and LUV. The 318 Poly (also know as the 318 wide block appeared in 58 in Plymouth. It was soon adopted as the corporate small block and continued in production into 1965 at least. It is a separate design from the lighter weight casting LA family 318. Are you with me so far? Dodge Polys are found in 241, 277, 315, 325 Cube displacement. Desoto's are .... hummina,,, hummina,,,,, $1500 for an incomplete mystery condition mill is quite frankly just plain silly. There aren't exactly rare, they are well built, parts take a little searching. Their production run was basicly 4-5 years, they existed in the shadow of the more exciting Hemi Engines and so there was not a great deal of performance development. Chysler quickly moved on to a more standardized designs that cost far less to produce and were lighter in weight, and then created still another design evolution. These are good engines, made with high nickel content iron. The machining was costly as well. Plus you get to explain what it is to your machinist. Only the really old crazy, bat**** guys that nobody ****s with know what they are and may have even done one. I just got of the phone with a respected local guy with 25 years experience and had never heard of my 315 let alone worked on one. I would really like to talk to someone who has done a Poly. You will have to get creative. And the scalloped lower edge of the head and valve cover are unique. Please see enclosed photo of my 56 315 Poly. It was an embar***ment of riches is what it was. They must have lost a lot of money doing it that way. ******* that Lester Colburt!
Thanks guys! No wonder I've been so confused about this stuff for so long - it's confusing. Now if I can just remember some of what I've read here, I might be able to have an intelligent conversation with some of my Mopar pals...This is why I'm on the HAMB...Thanks again (if this is accurate info - if not - thanks for nothin'!)........
I have a poly motor from a 58 D-500 it was a replacement for the more expensive Hemi. The block numbers can be looked up on the early Hemi site and you will find the early blocks are the same numbers as the Hemi. I was given this running 58 Dodge and the motor is the 354 block. Right now it is a two barrel but I plan on changing over to a four(same intake as the Hemi Dodge) this is a good looking motor and the standard ****** will make it all worthwhile. $1500, seems excessive and there are plenty of moters out there for far less. The cost of converting one of these is just too much.
354 Hemis run $500-1000. 1500 for a poly is excessive.Benzine440 your 315 poly is the same as the hemi except heads,pistons & pushrods. Go to webrodder. Doc Fromader has a buildup on a 315 Hemi on it. He uses an exotic stroker crank & cam, if you ignore that most of the rest is applicable to building your 315. Tex Smith's Hemi book goes through doing a 392, & there is a site linked to Bob Walker's Hot Head site that covers a Chr. build. Between them you should be able to get your engine done. The engine picture doesn't show well on my computer, but i'd get rid of that heavy generator & (if your staying poly) chrome those unique valve covers.
read this: http://www.jalopyjournal.com/forum/showthread.php?t=34833&highlight=poly+hemi and this: http://www.jalopyjournal.com/forum/showthread.php?t=14353&highlight=poly+hemi and this: http://www.jalopyjournal.com/forum/showthread.php?t=14269&highlight=poly+hemi
Opps, my bad. You're right on that. Like you said, the Desoto Poly's were Dodge based, and use Dodge parts for conversions. -Jeff
Thanks for the tips guys. I thought that the price was a little high on both the car and the motor. They are starting to get scarce around here. I looked for a 392 about 10yrs. ago and couldn't find one. There were plenty of 331, 354's and early hemi's still around but no 392's. Now there aren't hardly any Hemi's left in the local junkyards. There are still a few yards back in the mountains that I haven't hit in awhile that might have something tho. Will try to look around when the weather gets a little better and see what I can find.
As Far As Plymouth's Go, 56 Would Be The 277 Poly (the Little Brother Of The 318) The In 57 The Turned Into The Poly 318
According to my source in 56 Plymouth had the 270 poly (hemi block) & 277,303 on the revised Poly only block. 57 277,301,&318.
While this is still fresh, does anyone have a picture of the valve covers that say CHRYSLER SPITFIRE in the script like CHRYSLER FIREPOWER? Or was I dreaming when I saw them? BobK put some up that looked damn cool, but weren't whaat I was looking for. Jay
Actually that's the later Poly. The earlier poly mill (56/7) had a lot deeper scallops in the rockercovers. The covers won't swap. Chrysler from what I understand is the only company that called them a Polydine, Plymouth and Dodge called them a Polyshpere. As far a the SB Mopar goes the poly head was or is the easiest to make breath. When I was a kid the older MOPAR Gurus always wanted a poly just for that reason. The heads have ports to die for. Personaly for a hot rod I think it is the perfect mill. They will make plenty of zot and you'll almost never park next to yourself at a cruise. Hey Reg I think I know the guy that ended up with that mill. he thinks its gold.
obviously i don't know anything for sure about this as i was born in 58. BUT! this here 1964 motor's manual list the following: PLYMOUTH 1955 259 1956 270 277 303 1957 277 301 318 1958 318 & a 350? 1959 318 361 1960 318 361 383 then a RAM383,same bore,stroke,comp ratio,2 4bbls as the regular 383 but 35 more ft lbs torque at 800 rpm less. 1961 318 361 RAM383 only 1962 318 361 no 383's? 1963 318 361 383 426 DODGE 1955 270 1956 270 315 1957 325 354 1958 325 350 361 1959 326?(this motor 3.9531x3.312) a 318 is 3.91x3.31. 326 is 40 over 318. 1959 361 383 1960 318 361 383 RAM361 RAM383 1961 318 361 383 RAM383 1962 318 361 383 413 RAM413 1963 same thing but 413 goes to 426 CHRYSLER 1955 shows 301 331 hemi 1956-1958 all hemis 331 354 392 1959-1960 all wedges 383 413 1961-1964 361 383 413 DESOTO 1957 341 325 1958 350 361 1959-1960 361 383 1961 361. like i said, that's what the book lists. hope this helps but if it don't, well it's a cool book anyway...mel
Yes! 241 & 259, both built on Dodge hemi blocks. Can be converted using dodge parts. 259, build a "hemi that never was".
side note:the a 326 is actually a 324,but heck,we can´t make a new engine that´s smaller than the 325 we already have. also,the aluminum waterpumpand trans cover of the 60-80´s 318´s will fit the older 277.301.318.326 if you want to loose some weight. and as said earlier, the poly 318/326 has very nice heads,big and straight,easy to make some hp there. old poly info:the multiple carbed intakes of the early hemis should bolt on to a same cid poly. late dodge trucks whith hemi had the chrysler engine in them. early 58 desoto adventurters came whith a 345 hemi,very rare,later during the year,they got the b engine. I´ve gathered some info on my site:http://www.anderssonracing.com
the aluminum waterpumpand trans cover of the 60-80´s 318´s will fit the older 277.301.318.326 if you want to loose some weight. radiator hose on A 318 is drivers side, LA 318 P***. side!!
Chrysler poly-spherical head engines were first introduced in the 1955 model line in the base model cars. These engines gad a displacement of 301 cubic inches and were a favorite with the stock car crowd because of that displacement. The hemi head, for 1955, was a 331 c.i.d. engine. In 56 the base models received a 331 poly-spherical combustion chambered engine while the top of the line cars got the 1/8 over-bored 331 (the 354) The 354 was carried over into the 57 and 58 model years in the base model vehicles while the top of the line models received the taller-decked 392 with its longer stroke and increased bore size.
The Dodge NASCAR engine is (loosely) based on on the poly design. The canted valves and combustion chambers are similar to the poly. That setup makes more power than they could have with anything based on LA 360 heads.
CHRYSLER 1955 shows 301 331 hemi 1956-1958 all hemis 331 354 392 No, these were all V-8 engines but not necessarily Hemis. the '55 301, '56 331 and '57-'58 354 were polyspherical engines.
yes the aluminum pump has the outlet on the other side,I just said it fits on the engine,besides,the la engine have cast iron pump too,it didn´t get alum "wrong" side outlet till the 70´s
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