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Poly 318 Questions

MoparsOnly

MoparsOnly

The snozberries taste like snozberries.
Joined
Sep 24, 2015
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I'm thinking of doing a Poly motor. I have a few questions before I bite the bullet. First is the trans. do poly's and LA's share the same bolt pattern for the bell housing. The second is engine mounts, do the older mounts from a 65' ram bolt in or do I have to fab something. Thanks Guy's
 
64-66 poly will have the same LA bell pattern. Some older ones may also. As for mounts have no idea.
 
thanks for the info on the bell pattern 7. It's much appreciated. Trying to find out info on these is like looking for bigfoot.
 
Don't quote me , but I think the mounts are different as well . I kind of remember a buddy getting a 70's pickup that someone had put a poly motor in and it was sitting all wrong and the guy had given up on the project because of it . That's how my buddy ended up with the truck .
 
Hey guys, Talked to a Poly specialist, Gary Pavolich. Well he told me that I could use an LA block with very minimal work. Gary said I'd have to clearance for the pushrods with a 1/2" drill bit and use the Poly head gasket, thats all it is. I almost forgot Pistons have to be for Poly head. Oh Boy, going to build something really one off and super cool. I m thinking of blower running on e85.
 
What are you thinking of putting this motor in ? I remember you where looking for a Ramcharger seat base ( Obviously I replied to it ) . But it's not a Ramcharger is it ?
 
No its a 87 D150 factory 4spd Short bed. The Blower is just a thought. I was even thinking of a paxton maybe? don't know yet
 
Sounds interesting , I like interesting ! :cool: Are you thinking of doing a build thread ?
 
I guess I can do that, yes interesting. I have heard people call me that before. On the build thread I just don't know where to start, I'm so far away on even being close to show any start point or really any work that can be shown as of yet.
 
I can understand that and if your like me you don't think to take pictures while your doing something , you just do it then then think about it afterword's . I've done a lot of builds but I never think to document anything till afterword's . With my Warlock , I was in such a rush just to get it to the point I could start driving it that I didn't do a build thread . Then after I started posting some pictures of it people started asking me if I had one and would ask me all kinds of questions . So what I ended up doing was start a thread from where I am now then kind of back track as I continue forward on it . Because it's going to be a "while" before that truck is going to be done , done . Hopefully , I'll be able to post it so that's it's interesting and not to confusing . Like I said "Hopefully" . Maybe what you can do , If you have the pictures is start from what the truck was when you first got it and lead into where it is now and then slowly add to it as you go along in the future . It's just a thought .
 
Then That is what I'll do. I'll also list some of the stuff I'd like to do with it. Me and you are a lot a like. I want to get it driveable since I really need a truck in the household down here In good old SC. I use to live in NY on the east end of LI. Garbage pick up was an after thought, not here got to go to the local drop off point so, it piles up pretty quickly, besides need to get some lumber and stuff from the lumber yard to do some projects around the homestead. I've got a 318 in it with a rod out of the oil pan. and another 318 that I've been doing some stuff too, nothing major cam, lifters, intake, headers and a few little things. That will be it for a while. I still have to grab the poly heads and some other stuff at the local pick n pull yard. I'll start the thread a little later on have some stuff I've got to take care of.
 
Just found this site and joined and then saw your post. I have a series 1, 65 Utiline D100 (last of the 4-headlight model and the Utiline is a "Step-side" box). Mine is a 110k original mileage truck and while I absolutely love slant 6's I picked up a correct year poly to replace the slant 6. So, I appreciate your interest in the poly 318. My love of this engine began when my dad bought a new 59' Plymouth Suburban (station wagon) in early 1960. That is the car our family moved to Oregon with from the Midwest and knowing how the car was treated by my brothers, I gained a lot of respect for them.

I am still doing things on the engine which is on a dolly but so far I adapted a T-5 5-speed to it, made my own adapter and mated Ford 302-351 stainless steel headers to it. I have a P600 Edelbrock 3-2 barrel manifold that I made (2) adapters for. One adapter is a single four barrel plenum which will just be a short term mess around piece. The 2nd adapter I have mates my small Magnusen super charger to the P600. Other than that I have the usual off-the-shelf pieces like electronic distributor, Denso alternator, etc. I have the most fun searching for parts that are true bargains. Once I have this in the truck and everything running as it is, I'll pull the engine and do a rebuild. I found NOS TRW forged pistons on Ebay and picked up some oversized stainless steel valves. This will be a mild engine by today's standards but I'm looking at roughly 400 H.P with the supercharger but could easily be 425.

I hope my project gives you hope. You should join the poly engine group on Yahoo for sure. Lots of good help and support there. Good luck with your project.

- EM
 
From what I know of the Poly vs the LA 318.... the poly and the LA 318's share the OUTSIDE dimensions ONLY, meaning the engine mounts should be the same! The only thing I can see with engine mounts is on the poly, you MIGHT want to reinforce the stock ones! That Poly, is a heavy one! It weighs damn near if not more then a Mopar Big Block RB!!!! -YES, they ARE heavy! As mentioned, the 727 Torqueflite should bolt right up to the Poly.... No issues as long as its '64 or newer, the older ones I think used a pre-727 tranny.....

NOW, performance-wise, your gonna need DEEP pockets, and a VERY THICK wallet. Those sorts of parts for the Poly engines aren't cheap! None of them have ready made performance parts that are one easy to get, and when found, NOT cheap! -NOW, unless your good with a TIG welder and a good metal bandsaw, your going to be having A LOT fabricated to fit anything to it.....AS I'm not sure ANY intake was made for the Poly's for a blower, and I don't even think a tunnel-ram was made for them either! I KNOW recently that a true "Air-Gap" intake for a single 4 barrel was made, BUT years ago, they made "Offenhauser" I THINK, made a 2, 4 barrel intake, BUT we're talkin' EXPEN$IVE if you find one! So that means you got the choice of a single 2 barrel intake, a single 4 barrel intake, and a dual 4 barrel "2x4" intake. BUT, good luck finding any one of the later units, the 4 barrel are rare and the 2x4 barrel is even more rare..... I do not believe ANY true Tunnel-Rams were EVER made for the Poly's, but I could be wrong!

As far as exhaust goes, you have the log exhaust manifolds (which would choke out the power from a one lunger John Deere tractor engine), and I know someone made headers for the Poly engines, I just can't recall who I read about doing it..... TTi maybe?

Pistons? forget it! (I know someone that just had special made pistons done for those engines, the Poly 318) and that is a task within itself, as the valve recesses are twisted & canted, which takes a counter mold putty type stuff, to form in the cylinder combustion chamber to make and then be removed and sent away, for the new pistons to be forged from.
Crank, I know some also makes a crank to "stroke" the 318 to be a bigger C.I.D, but again, I'll be damned if I can remember who....... I KNOW, if you bore & stroke a Poly 318, you can get something like a 402 cubic inch from it without any dangers.... Those Poly blocks are BEASTS and have A LOT of meat in them!

Heads, No one makes anything for them that I know of, BUT again because they're so heavy and meaty, you can hog out a lot of cast iron and gain a TON of flow..... BUT you gotta know someone that KNOWS Poly engines and how far to go! Same with boring and stroking.... Bore to much, and get to close a water jacket and cause overheating issues.... OR hit an oil passage, and still ruins the engine! Same with the heads..... Then have a valve reset done, and get a good valve job and damn good seat work too. You wanna blower, you got to look in the engine as a "whole" not just part of it, thats an OLD motor, be sure to have the block sonic'd first, and REPLACE ALL the soft plugs! I'd even go as far as to replace the head bolts with studs if you get to the point of supercharging that thing!

STILL tho, left alone, they got 230 HP stock, and will last forever if simply rebuilt in stock form.... Remember, those Polys being old, there isn't much out there for them if something is done wrong...... Your outta motor that won't be easily replaced! SPECIALLY if you have to set up the frame to take that thing as then your right back to "righting" the frame for a different engine!

SURE are Poly's cool? Damn right they are, but they are far and in between to find these days! BUT remember they were used in an assortment of applications just not Mopar auto's! Farm tractors had them in them (I can't remember the combine they were used in specifically,) AND power generators used them, for small industrial buildings, Boats used them, (smaller ones) and an assortment of equipment used them..... Portable generators, portable welders, portable water pumps as well as stationary water pumps, and I'm sure I haven't even touched the full list that used them, and may STILL be using them, those engines were built to last!

All I will say, is "GOOD LUCK"..... Can't wait to see and or read where you take this!
 
Just a couple of pics of my set-up.

- EM

Engine.JPG


Manifold.JPG
 
love the manifold and the header adapters. I'm kind of thinking about the same thing with my intake but using an LS version cut up some with a supercharger adapter on top. I'm going to use some LS headers with adapters kind of like yours. Keep up the good work.
 
Another case of poor judgement at the time. In 1973 when the poly threw a rod and took a chunk of cylinder wall with it. The solid lifter cam, lifters, push rods, freshly done cylinder heads with factory adjustable rockers and four barrel intake went to a new home for a mirror $75. Instead of retaining these parts I have moved for 42 years a set of early 64 bb/rb hp heads around that were polished ported, larger intakes installed, racer brown spring, port matched along with the 590 solid lifter thumper and lifters. If by chance some day I get to build a new bottom end for the later parts they will be used again. I had way more invested in them at the time than the poly parts and the bb engine was running. 42 years later I wonder if that discission was the right one?
 
didn't really want to start the engine electrical glitch starter wouldn't turnover the engine noticed a yellow wire disconnetd at the main terminal hooked it up bumped the starter dam thing immediately started has a cler fuel filter the gas was really brown from varnish at the auction cars were sold as is they didn't attempt to start them
 
-WOW..... Thats awesome no less, but I'd go through that thing rather quickly and get things all up to snuff.... Specially if ya wanna keep it as-is and running, unless you plan to take it out put it down for a rebuild and keep the car original. -Those were the "Grocery geter" engines, they wouldn't win a race, but I can tell ya, you would get there no matter what!
 
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