I have a 326 A-block Poly engine in my 59 Dodge Coronet, it's the original engine & only has 29750 miles on it... I am in desperate need of someone that rebuilds them OR where the hell to get a rebuild parts kit for it? I just had the engine gone thru, new tank, fuel lines, rebuilt power steering pump, radiator, etc, etc.. Started it & it starts knocking bad, shut it down and now I need it torn apart!! So much for trusting THAT mechanic again... I'm about replace it with a bowtie 350 (no not really, just frustrated...Sorry Chevy guys/gals it's a joke). A 325/326 is a crappy engine and it has been giving me nothing but grief since 2004. Or if anyone can suggest where to get a turnkey crate 318. I want to keep the push-button transmission set up & don't want to have to modify it. I'm not looking for power just reliability. Thanks HAMB family!!
As far as I know the 325 poly is just a 318 A series poly bored 40thou over.......whats the knocking from?............I see rebuild kits advertised on US ebay, pistons,rings, all bearings, timing gear & chain, valves, lifters etc everything for less than $1000.........get a workshop manual, pull the engine out and find out whats wrong, get it repaired and assemble it yourself, I did 40 yrs ago with a workshop manual & basic tools, still going strong...........they are just an early version of the LA 318........same basic bottom end but different heads & intake............ try Super-Pac ph 888 548 2282 in Quinlan, Texas, they have various engine parts as well as intakes, exhausts, cams and other hipo gear & should be able to help one way or the other............Tex Smiths "The Complete Chrysler Hemi Engine Manual" by Ron Ceridono is worth getting as it has a complete chapter on rebuilding the Plymouth 318 Poly which is what you have..........if you do find a crate engine make sure that its a pre 1962 version as these have the crank flange using 8 bolts to suit the cast iron Torqueflite that you have........1962 & later Polys use a 6 bolt flexplate and if the crate engine has this setup it won't allow your converter to fit............andyd
Some good info from andy there. Parts are available but you just have to look harder than for SBC and SBF parts. Why not take it back to the mechanic that worked on it? What did he actually do to the engine? If something he did has caused the knock them let him fix it. May only be a simple problem. Good luck with it.
Just to offer (I think) a bit of clarification........there are TWO engines that are being referred to as 325 and/or 326. The first 325 was a direct derivative of the Dodge 241 hemi of '53/'54 that was enlarged to 270 for the '55 models. It was also produced in a poly head version of 241, 259 and 270 cubic inches. In '56 models the deck height was increased to accommodate a longer stroke and 315 cu in models were offered in both hemi and poly versions and for '57 it was increased to 325 in both hemi and poly versions. The 325 poly was used in both Dodge and Desoto in '57. The OP's engine, which he refers to as a 325/326, is a different engine that was derived from the 277/301 cu in Plymouth engines introduced in '56 models. It went on to become the 318 and, apparently, a 325 or 326 cu in version as well. The key difference in identifying these different families of engines is the valley cover/intake manifold. The early A engine (241 thru 325) have a tin valley cover and the intake manifold arches over the valley. On the later (277, 301, 318, 325/326) the manifold serves as the valley cover as well. Also, the upper water neck on the early engines exits from a water 'manifold', whereas the later engines (as pictured in the OP's post) the water exits from the manifold itself. Most likely none of this matters much, but I just felt compelled to clarify the differences in engines casually referred to by the same 'name'. Ray
Ray, thanks for the extra info, here in Oz we only ever got 301/313 & 318 versions of the Plymouth A series Poly engine and the pic of the OP 's engine clearly identified it as the Plymouth A series version via the rocker covers & intake manifold........a mate a few yrs ago had two of approximately 20 1955 US Plymouth 4dr Sedans that were imported into Oz when new, both of his had the early Poly with the even more distinctive "scalloped" rocker covers and separate intake & valley covers & provided an interesting comparison between the two Poly versions of his cars and that in my 1940 Dodge........the Chrysler Australia assembled 1955 Plymouth, Dodge & Desoto vehicles were all 4dr sedans & Utes based on the 53/54 Plymouth body shell and all used either the 230 or 250 cube six depending on the gearbox selection...........another suggestion for the OP if he is fed up with poly problems would be to install an LA series 318 & 727 auto, keeping it at least in the mopar family..............andyd
with all the new parts being made for the poly 318, (Toth Performance is one source) and the 326 bore size being .040 bigger than a 318, new life for the dead as they say. I can find the ph. no. for Toth if you need it, but they are in a lot of the Chrysler Power magazines on the shelf at Books A Million.. You can get a feel for the power they are getting out of the polysphere
what Ray said....it's an early 318 you have there....not to confuse with the later poly 318 - they had a different crank....if you want to go with a newer poly 318 and later trans it's not that hard....I have a 1956 - 277 in the Fury - runs great - a 1965 318 poly in my station wagon - runs great - 1966 318 poly in my D300 truck runs - but could use some help...maybe you been mislead or the mechanic doesn't know what he's doing....
Hey I think I have a friend who can help. Just call (253) 631-8643 ask for Brian. Sent from my iPhone using The H.A.M.B. mobile app
Ray, This was the only reason I called it the 325/326. I'm still learning things about this engine on a daily basis. Thanks for you advice too!! Mike 326 The 326 was launched in 1959. Its actual piston displacement is 325.2 cu in (5.3 L) but it was marketed as a 326 to avoid confusion with the Dodge Red Ram 325. The 326 uses the same 3.31 in (84.1 mm) stroke as the 318, but with the largest bore of any A engine at 3.95 in (100.3 mm). It uses hydraulic tappets, unlike the earlier A engines, and was used in the 1959 Dodge Coronet.
Swifty, Main the the mechanic did mechanically was all new fuel tank, fuel line, install petronix ignition (POS in my opinion) does not start any better than the points/condenser, pulled a plastic O'reilley auto parts bag outta my radiator. So pretty sure he didn't do anything but sure don't trust him enough now to take it back to him. The knocking sounds like connecting rod. But I really don't know enough to know for sure.
Andy, Thanks Mate for all your advice!! I will call the guys in Texas to see if they can help me. I haven't had any luck at all finding a rebuild kit anywhere... I've looked (eBay, etc) & still nothing. I can't even find a pre-62 crate 318. That's why I wanted the see what my HAMB family knew, cause I'm outta options. I want my Cheetos & grape nehi 59 to have a reliable heart for a change. Sp thanks to all of you & still keep the advice coming please!!! Thanks!!! Mike
Mike, just checked US ebay again under "Plymouth 318 Poly" in Car Parts & Accessories..... are you looking under Dodge Coronet?.........anyway there are 63 listings ranging from rocker covers and new decals to a twin four intake, various engine kits ranging from complete kits with pistons,rings, all bearing, cam, oil pump, valves, lifters, timing gears and chain & full gasket set..then there is the separate sets of valves, engine mounts, ignition and carby parts........lol...........heaps of bits.......lol........but as I mentioned previously I don't think you will find a Poly crate engine of ANY sort, just don't think there would be sufficient demand............btw my 1940 Dodge 318 Poly uses a Mallory twin point dissy that was to suit the later LA series 273/318/340/360 and if you want you can bolt into the 318 Poly any factory Mopar LA Series Electronic Ignition kit, the dissy mounting is identical............ I mentioned Super-Pac in Texas previously, just checked their advert in August Chrysler Power mag & they list intake manifolds, headers, solid and Hydraulic cams, Engine parts incl gaskets, Big, main & cam bearings, oil pumps, pistons, rings, alloy rocker covers(worth getting to stop the poly habit of expanding rocker covers when the 2 bolts used squeeze the covers out), oil pans, etc, etc..........even STROKER kits....402 Cubes of throbbing POLY.......just noticed they have a complete Mopar Performance electronic ignition, dissy, leads, module, bolts in for $259.00 US............mate its POLY heaven over there........lol.........get with the program!!............lol...........all good, will go take my meds now............heres a pic of my Poly........ regards, Andyd
So as long as I don't change the piston's everything for the 318 should work then I'm guessing. From what I'm researching the only difference is the bore. I'll tear it apart. I'm forced to put in on the back burner until I get the 217 reinstalled back in my 48 Plymouth. I guess this best thing to start looking at it drain the oil, flip the engine and see if it's the connecting rod that's making the noise. I just hope it's something simple, but it never is with this old Mopar's. LOL. So this Chrysler Power mag is helpful? I'm going to call Super-Pac in Texas next week & see what they can do for me too. Thanks for all the advice! Mike
Mike, the Chrysler Power mag covers all sorts of mopars but over the past couple of years they have been at the forefront of getting a newly designed intake manifold made as well as alloy rocker covers and seem to have inspired a few companies to start either making bits or at least mentioning the Polys in adverts.......the only bummer has been the recent death of the Publisher of the magazine, Roland Osborne, it was he who seemed to be a strong advocate for Poly development, hopefully the others involved will continue to carry the torch.........also do a search on the Hamb threads as there have been quite a few over the years.........andyd
I'm looking at your engine & mine at the same time. Despite the obvious of the difference of air cleaner cover, valve covers & some other minor things are they the same? Is yours a 59 318? Reason I ask the intakes look different. Also how do I know for sure mine is a "poly". Is it the serial number on the block or some other way, just curious. Still trying to learn. This way when I call that shop you suggested I tell them exactly what I have. And hope like hell they can rebuild it for me or at least tell me someone that can. I got to have her ready for next April for the Lonestar Roundup in Austin, Texas. You get time look it up. Best car show I know of!! I'll go get me a copy of Chrysler Power & Hemming's this weekend & see what I can find for Mopar, until you mentioned it I forgot about the adverts in Hemming's to get help with my car. I'll check on HAMB more too! Thanks Mate! Mike
Mike, the engine in my car came from a 1962 Oz Chrysler Royal, these were 313 cubes which is 40 thou under the 318 size, however 40 thou OVER in the 318 bore size gives 325 cubes and my car runs 40thou over 318 pistons, I just had it bored 80 thou to make 325.........as far as what makes a Poly.........its the way the valves are arranged, its essentially a cheaper way to obtain "hemispherical" combustion chambers without the extra expense of using 2 parallel rocker shafts .......what mopar did was to use a single rocker shaft and have one set of rockers pointing towards the carby and another pointing towards the exhaust manifold.....by doing this mopar had almost the same benefits of the "hemi" combustion chamber without the expense.........mopar polys are easily noted by the shape of the lower , exhaust side of the valve or rocker cover........the initial 1955/56 Plymouth Poly had scalloped lower edges to the cover to clear the rockers inside, the Chrysler, Desoto versions had a similar shape cover..........but in 1957 Plymouth changed its Poly covers and intake manifold to covers with a "saw tooth" shape to the exhaust side and used a one piece intake that covered the whole valley between the heads.......and it is what both your car and my car use, just that I have a Weiand Single 4 alloy intake and Edelbrock alloy rocker or valve covers.........this Plymouth 318 Poly was kept the same till 1966 or 67 in the US so any external parts will fit your car.........take a look at the rocker covers on your car and intake manifold, then just do a search on the net under Plymouth or Dodge 318 Poly and you'll see lots of them.........but if you don't include the "Poly" bit then you'll get all the later Mopar 318 engine which is not a poly, it has the same block but different heads, intake & exhaust manifolds...............anyway trust this helps a bit........regards, andyd
Check out the engine masters vintage division. There are guys that are getting insane numbers from poly engines. Maybe one of those shops can help out.
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