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Se7eN_(YANKEE)
05-02-2005, 09:17 PM
The 1957 fury came out with the 318 wide block semi hemi, It was a wide block of course but the heads had polyshperical chambers just like the hemi head except smaller. how much power could this engine put out and could it live up to its brother the hemi. the reason why i ask is i found one, A full long block untouched out of a 58 dodge suburban miles unknown.And a how much would one of these babys be worth.

Thx Se7eN

nhdriver
05-02-2005, 09:29 PM
They can be made to perform well, But the newer "LA" style engines have been developed further and peform far better, The old Poly engines are ancient technology. The "LA" engines will give you far more bang for the buck.
As for value, not much unless you are restoring an older vehicle

Se7eN_(YANKEE)
05-02-2005, 09:37 PM
never really seen the 318 wide block but im asuming you can't put those heads on an LA block.

sanborn
05-02-2005, 09:57 PM
The early polysphere block is the same basic design as the Mopar industrial block. The industrial block was sought after in the 70s(prior to introduction of the X block). Why? The industrial block had thick cylinder walls, some(very few) actually had 4 bolt mains. It was a good race block in its day.

The LA heads would bolt right on the poly block. I assume the poly heads would bolt on any later LA block, don't know for sure.

Don't know anything about the poly heads. They weren't as good as LA heads(so I have been told).

peg leg
05-02-2005, 10:14 PM
Those old 318's were widely used in boat power applications. They were so big they looked like 413's. They lasted forever, and many are still in use in Alaska. A friend had '64 Glasspar Meridian cabin cruiser with a 413 that lasted 20 years in salt water before giving up. Chrysler "owned" the marine engine business back then. Sure would like to see the 4.7 and 5.7 back on the water!
Ron

nhdriver
05-02-2005, 11:38 PM
se7eN, You seem to be under the impression that the 318 Poly heads were some kind of Super Duper performance head , They are not 340 heads or any of the performance heads available for the "LA" engines will blow away those old Poly heads. Hemi heads they are not! performance wise or otherwise.

TK
05-02-2005, 11:47 PM
se7eN, You seem to be under the impression that the 318 Poly heads were some kind of Super Duper performance head , They are not 340 heads or any of the performance heads available for the "LA" engines will blow away those old Poly heads. Hemi heads they are not! performance wise or otherwise.

they are closed combustion chamber canted valve heads, way better idea than the inline heads (LA) but dodge saved some space.
the most stock HP a chrysler 318 ever prodused was the 58 318 with dual 4bbl, it made 320 HP i believe (more than a 340 even).
cant beat em for performance, just find parts for em.

Billydelrio
05-03-2005, 12:08 AM
The way I see it, the problem with the Poly head was the single rocker shaft with the intake and exhaust rockers facing opposite directions. The ports actually flowed decent, but you could not open the valves much and maintain a reliable rocker arm geometry. Relocating the rocker shaft took some serious effort as the shaft pedastals were cast to fully enclose the shaft and were also the head bolt boses. It is easy to install longer valves and relocate the shafts on the LA heads, but on the poly head, ouch. Then there is the overlap problem. The exhaust valve opens straight down into the cylinder and the intake is canted to open towards the center of the cylinder, towards the exhaust valve. If the heads are opened up for larger valves, a wider LSA cam needs to be used.
There is a fellow named Gary Pavlovich, who used to frequent this board, that tinkers with the Poly. I sent him all my old poly rockers and stuff a few years ago. I just never got around to sending him this last pair of heads. These heads were worked over and raced on a 4.015" bore 335 cubic inch 318 block. This engine had an Isky 505C hardfaced overlay cam, tunnel ram with two AFBs, good headers, high dome pistons, a serious late 60's race engine effort. In the same car, my little 273 ran quicker and faster. My 273 did have a CC292 hydrolic cam, 1.88/1.60 valves in 273 heads, and headers.

Dick
05-03-2005, 12:47 AM
the most stock HP a chrysler 318 ever prodused was the 58 318 with dual 4bbl, it made 320 HP i believe (more than a 340 even).


Actually, the dual quad Fury 318 in 1958 was rated at 290 HP. The dual quad 350 was rated at 305HP.
:drool:

TK
05-03-2005, 02:39 AM
ok, hers what i got, the single 4bbl. 58-62 318 was 260HP

and the 57 @ 4bbl was 290

thatnks dick. you have to admit, with 50's technol;ogy, 290 HP was impressive! :jawdrop: :jawdrop: :jawdrop: :jawdrop: :jawdrop: :jawdrop:

Dick
05-03-2005, 03:42 AM
ok, hers what i got, the single 4bbl. 58-62 318 was 260HP

and the 57 @ 4bbl was 290

thatnks dick. you have to admit, with 50's technol;ogy, 290 HP was impressive! :jawdrop: :jawdrop: :jawdrop: :jawdrop: :jawdrop: :jawdrop:

And the single 2 bbl was 230HP. I won't argue the impressive issue. My dad had a '60 Dart with the 4bbl 318 and Torqueflite and I cleaned a 300 HP 352CI stick Ford Galaxie with it in a 1/4 mile street drag.
:drool:

TK
05-03-2005, 03:56 AM
the trucks i have ran with wideblocks were really powerfull, better than the LA in stock form.

DartGT66
05-03-2005, 05:08 AM
There was two reasons for dropping out the poly; price and size. It was not dropped out beacause of a greater design, but because it was more expensive to build and needed more room. Imagine an A-engine in an A-body, it's a tight fit. The block height of the poly, and therefore the width is pretty much the same as in the later LA engine, but the difference comes from the heads that continue in V shape while the LA heads continue vertically from the block. The poly chambers are not closed chambers. The exhaust valve angle is zero and intake valve has a slight chamber. The arrangement resembles slightly that of the BB chevy, 385 and cleveland fords. The heads really do not have that much potential, tehy do not flow very well and can't even easily be made to flow similar amounts as the newer LA heads. But still they can make respective power and very good torque. I think the old power ratings may be a little overrated if you compare a 290 hp 318 for example to 275 hp 340. Take a look at the poly exhaust manifolds; they look like they could flow about 110 hp's worth. I had a poly in a '65 Fury, and it performed very well in it.

Se7eN_(YANKEE)
05-04-2005, 09:01 PM
I like all the replys, i think im going to buy the long block and test it out, thats the only way to know what BS is right and wrong. :jackbox:

sanborn
05-05-2005, 11:59 PM
I have only taken apart one 290 HP, Poly 318---and it was years ago. It was a 2X4 intake engine, with a factory solid roller cam. Not exactly a "standard" type engine.

TK
05-06-2005, 12:01 AM
I have only taken apart one 290 HP, Poly 318---and it was years ago. It was a 2X4 intake engine, with a factory solid roller cam. Not exactly a "standard" type engine.

what do you mean standard? :shrug:

eckertt@epri.co
05-06-2005, 01:50 AM
In the mopar performance book on "racing the small blocks" they briefly talk about the 318 poly engine. They say it was a great engine, but they also advise against doing anything to it (hot rodding) due to the lack of vendor support. Seems that very little "race parts" are available for this engine. (Per the book.)

Tim

DartGT66
05-06-2005, 03:39 AM
solid roller cam in a poly 318? No way stock, there is propably no roller cam cores available for the poly either. All polys had solid lifters, but you can also use LA engine hydraulic lifters with a poly hydraulic cam grind and slightly shorter pushrods. Ther is not much "hard" parts available for the poly. TTI has headers for some bodystyles, and Spitfire used to make less expensive headers for tehm, but I don't know about the reliability of the company. You can stroke teh poly with a modified 360 crank or the 4.00" stroke cranks and usually bore it to 4.00" without any problems, tehn it's just going through piston catalogs and finding a piston with proper measurements. Lot's of possibilities in teh 4.00" bore size. Propably have to make valve reliefs to the pistons. If you can supply the old camcore, any cam manufacturer can grind a high performance profile on it. Chris Neilson cams offer new performance cams for the poly. Weiand has a single plane four barrel intake for a square bore carb. Custom oversize valves can be had from Ferrea. LA-engine distributors and many other parts fit. It requires a little more studying, but a poly can be built to a pretty serious street engine. It will cost a little more than building a LA, but what is the cost of personality?

Se7eN_(YANKEE)
05-06-2005, 03:34 PM
In the mopar performance book on "racing the small blocks" they briefly talk about the 318 poly engine. They say it was a great engine, but they also advise against doing anything to it (hot rodding) due to the lack of vendor support. Seems that very little "race parts" are available for this engine. (Per the book.)

Tim
I have that book and it also states that the stroke of the 318 A engine is the same as the 318 LA engine. So to my understanding the short blocks are almost the same. I was thinking about boreing it out and changing the stroke abit and puting the right compression height on the piston and maybe turning it into a 360 wide block with poly heads, and yes im sure i will have some porting and polishing to do on the heads. (So i a sence i will be stroking it out)
Im going to need custom parts for this engine anyways so it will be a few years probalby till it will be done.

Se7eN :dude:

Dick
05-06-2005, 07:01 PM
There used to be a 3-2bbl manifold for the poly 318. I think it was made by Weiand. I had a buddy with a '61 Dart Phoenix Hardtop that had one. It really looked impressive and moved right along. :drool:

SixGunner
05-06-2005, 07:18 PM
http://www.1962to1965mopar.ornocar.com/poly318.html

There's always gonna be naysayers. True, it won't benefit from the YEARS of development the LA aftermarket has, but it can be made to be respectable. In an early car (pre 60's) it'd be right on. Or a street rod. But in a "musclecar" you would be ahead to go with a 273/318/340/360.

I would like to do a "Spitfire" Poly up in an early 30's Ford. Someday...

If it's cheap enough and you're bored enough, go for it. It'll keep ya busy.

There's also a section in Tex Smith's HEMI book on them. Unfortunately, it looks like the 318 Poly is one that can't be turned into a HEMI, but it can be made pretty bad ass, and it'll look different too.

My 2 cents, FWIW.

Jay

sanborn
05-06-2005, 10:15 PM
Dart, maybe I was trying to be too cute with my comment about the roller camshaft in the 290 HP poly engine. The engine we took apart really did have a roller cam and was supposedly a factory engine. It did have a factory 2X4 intake(cast iron) with two Carter WCFB carbs.

In the late 50s, several factory engines used aftermarket performance parts. For example, the 312 Ford engines used Isky EE3 solid lift cams/lifters/springs, etc. as factory parts. Studebaker did the same. Maybe the factory "race" 318s did the same---I don't know.

Also, I made an earlier comment about we sought early industrial poly blocks as race blocks for LA heads. Everything in a poly 318 block(cranks, lifters, rods) will interchange with later 318/340 blocks. Cranks are the same(dimensionally). The industrial poly blocks are quite a bit heavier than later LA blocks. We had the best success getting industrial poly blocks out of combines and stationary engines. The marine blocks were the same as regular car poly blocks.

My memory is getting "foggy". Maybe I need to look in some of my 57-58 magazines.

sanborn
05-07-2005, 12:11 AM
Went down into the basement, looking for info on the 318 poly engine. Didn't find exactly what I was looking for, but this is close.

This is from the HOT ROD ANNUAL(1958) in an article entitled "Chrysler Corporation Power Plants for '58". There are several pages in the article--mostly describing the new 350/361 Big Block engine. In a paragraph describing all the optional intake systems, it has the following:
"Plymouth is still using the 290 horsepower, 318 cubic inch engine in their Fury models. This engine differs from their other small Plymouths in that it has a 9.25 to 1 compression ratio instead of 9.0 to 1, two four throat carburetors, a double-breaker point distributor, a special camshaft that is very different from either of those offered with the regular engine and dual exhaust system."

That's all the info the article had about the '58 318 poly engine(290HP).

I'm not trying to "beat this dead horse". I am trying to point out that some of the Hi-Po engines of the 50s were pretty radical, and the 290HP poly engine was radical for its day.

Other info/corrections, etc.---the Isky cam used in the HiPo 312 Fords was an E-2. And, the 3X2 intake offered for the 318 poly was an Offenhauser(found it in an Almquist Catalog). Nothing was listed by Edelbrock or Weiand for the 318. For what it is worth, if Offy ever offered something(like an intake), they still will produce it by special order.

Se7eN_(YANKEE)
05-07-2005, 05:43 PM
Thx sixgunner for the link. Im sure i will have a great time building this engine.

Se7eN

Stoga
05-07-2005, 06:04 PM
The heads really do not have that much potential, tehy do not flow very well and can't even easily be made to flow similar amounts as the newer LA heads.
I'll have to take issue with this statement, we flowed some Poly 318 heads and in some cases they flowed better than J heads. They'll respond to the same tricks as oversized valves and a decent porting as any head.
They wont be as good as aftermarket aluminum heads, but then again, neither are most iron production heads.
I think they have enough potential to make a decent vintage rod engine or will heat up good enough to make an early Fury or Coronet run decent.

pishta
05-07-2005, 09:52 PM
500 HP is not unobtainable with these motors. Lots of stroke and custom piston potential along with larger valves and such (Poly head looks alot like the new 4.7 head). Gary down in Santee, CA Makes em (do a GOOGLE on 318 poly) and he was stung by Harold of Spitfire headers too! Had a dateline 1 month that said headers would be here in two weeks, next dateline was 2 months later and still no headers....

TK
05-08-2005, 02:39 AM
anyone has ever driven a A, please say I, cause the ones i have drove ran like stink, even with a lil 2bbl. the 4bbl ones are amazingly torqey for a 318. i know of a 315 in a 57 pickup that has 3 2bbl intake, isky cam, porting, polishing, and it is faster than most of our cars :toast:

cutting torch
05-08-2005, 09:16 AM
My brother had one in a '66 D200. Even with one dead hole it had great torque. I say go with the 4" crank, and build it for torque!

torch

Se7eN_(YANKEE)
05-08-2005, 02:44 PM
the bigger the better. I have the engine blue printing book that was writen by rick Volegh, i think thats his last name. But im going to use some of his techniques for some great testing in how many rpms i can make.

Se7eN

benno318
05-10-2005, 07:52 PM
theres a group for anyone interested, all they talk is polys. its been quiet for the last few days, so get over to http://groups.yahoo.com/group/318poly/ and get the guys talking again, plenty of good ideas there and you can sign up and let us know how you proceed with yours.