Is The 318 Polysphere Mopar Popular?

Is the 318 Polysphere Mopar a popular engine? I stumbled into one, and I'd like to know what you think about it.

 

They are for me. I built a T-bucket in 1962 with one in it (still have the T) and just finishing off a 32-5w with one in it also. They wouldn't be popular where you're at cos there's so many SBC's available and they're cheap to buy and rebuild. Polys are cheap to get (giveaways) but not cheap to build and speed parts are definitely not cheap. Oh and they're big buggers too with close to the weight and size of a Chrysler hemi. If you send me your email addy I can send a couple of pics, not smart enough to post on here.

I just tell folks it costs to be different.

 

There are some Poly motor gurus on here, great motor but they weigh a ton, I've got one sitting waiting for some attention. There are a lot of LA 318 parts that fit them straight out of the box (timing gear, dizzy etc) and some that'll fit with a bit of massaging (offset ground 360 crank). Intake manifolds will be the hardest to find but you can get 1x4, 2x4 and 3x2 setups for them, I've seen Hilborn injection as well. Good luck.

Scotty

 

Not popular at all, to me they are a good motor that was under rated. They had a lot of potential but Chrysler did not support them in a performance role. They had the Hemis for that, from 1951 ot 58. Then they had the B and RB wedge head big motors. They were practically the same size and weight as the poly with nearly 100 more cubic inches (318 vs 413).

The performance 318 lasted only 2 years, 1957 and 58 before being detuned and relegated to workhorse duty in big sedans and station wagons.

 

Popular? Uh, no.

But they are a great engine. Definitely heavy by small block standards, although they're lighter than their hemi predecessors. Still capable of making plenty of horsepower too, and a lot of the later smallblock stuff will bolt on.

As has already been pointed out, it won't be cheap to build. But, it will be different than what everyone else is running, and the sawtooth poly valve covers give them a unique look.

 

I have had a 1962 318 Poly in my 1940 Dodge since 1973,, its +40 thou so its 325, still has the cast iron torqueflite attached. I had an original 57/58 factory twin 4 intake with a pair of Offy crossram adaptors and 600 Holleys sitting above each rocker cover, big cam etc.......eventually sold that off and have had a single 4 Weiand alloy intake & 600 Holley since about 1980.........still has it but I've recently got another cast iron twin 4 intake, a pair of edelbrock carbies & a fake Magneto...........lol..........back in the 80's I was looked upon as strange........lol........now am still strange but much cooler............lol..............andyd

 

I can help you out with some pics swifty, a story I did with swifty a few years back
<iframe src="http://www.youtube.com/embed/hYcP7TWXPlw" allowfullscreen="" frameborder="0" height="315" width="420"></iframe>

 

Thanks for that Murray- just shows you're smarter than me LOL

 

My buddy had a 318 290hp in a 57 Savoy in 1957, thinking it was hot he ran it at the drag strip...he was out run by a 57 golden hawk and a 57 270 chev.........!!

 

These are good engines,If you had a mid 60`s mopar the poly was in most of them as a base eng. Belvederes ,satellites,coronets,& even Chargers. When I was a teenager I beat the hell out of them & the just kept running. These eng have alot of potential for sure. You can get most parts from Napa stores & EGGE has pistons rings,bearings etc. Theres even a couple cam compainies that will grind you a cam. Headers are a different story,I`m just making my own. My father machined up some header flanges & were just going to fabricate from there. The Biggest killer to these engines for power is thier Log ex manifolds! Currently I`m building a 33 Dodge coupe with my father & its running a 57 plymouth 318 fury poly eng. Cant wait to take it for a ride with the 3 duece setup on her.

 

If it was not tuned properly, had high rear gears, slipping trans, poor traction etc, it is not a fair comparison. One of the guys at a local speed shop used to run consistent low 13's with a poly in a '63 Dodge 330 with only a few mods like traction, 3.91 gears, cam and 4 barrel intake.

Don Dolmetsch here on the board has a ton of experience with these very cool engines - he might just check in on this thread . . .

 

AND if ya don't have a set of those valve covers...I have a nice pair listed for $60, but for guys in this thread I'll knock off a saw buck, lol. But seriously, it is underrated, a nice change from a SBC for a rod and you can bore the shit out of them .80 with no problem. Some LA parts will inchange (uses big block spark plugs) and has what is called the semi-hemi heads. I had one in my 65 wagon with no problems...be different, enjoy.

Don

 

Any pics of those valve covers? Might be interested.

 

The Poly 318 was buiilt from 1958 - 1966 in US-built vehcles, and held over one more year for Canadian builds. These engines were also in light and medium-duty trucks, as well. Used to be a local guy that had a dual-quad 318 in a '66 Charger, with an automatic and 3.91 gears that would scare the crap out of ya! His was the definition of a sleeper - tan, steel wheels, no hubcaps, relatively quiet Hemi mufflers...looked like Grandpa's Charger, but that Poly engine made belivers out of folks!

If any of you guys are building a Poly 318 for a Dodge Sweptline pickup from 1961 - 1967, there are custom headers available for that specific application, and can be ordered painted, coated, or chromed. The guy that sells these had a lot of 50 pairs built. When they sell out, that's it!

 

The Poly was a grandma engine for decades...they've recently become popular as a hot rod engine. Who'da thunk it?


"traditional" is a strange and mysterious thing

 

You are better off making your own, they will fit and work properly if you do it right.

They ain't cheap, but TTI makes these for poly's in B-body mopars -





http://www.ttiexhaust.com/Header-TTI318BC/Polyheaders.htm

Looking at the driver's side header, that back tube is about a foot short of everything else - you would think for the money these cost they could at least be equal length! And how many 318's can use a tube that big? (1 3/4") 1 1/2" is more like it unless you are boring and stroking it and revving it out to 7500. On second thought, don't bother with these!

 

Yep, I have them listed in the HAMB classified under
"318 Poly Valve Covers"

Don

 

Interesting.... I think I'll hold onto it a while then. I got it with a '63 Sweptline that I bought for the WW2 WC axles and transfer case that a farmer had installed under it. The 318 that came with it is encased in 2 inches of oil and grease and looks like its a boat anchor. Imagine my surprise when I put a socket and breaker-bar on the crankshaft pulley, and the motor spun over with the smoothness of silk. I'm betting that if I tune it up, it will fire right up with no problems. Depending on how it sounds, it might go into my '50 Ford until I can rebuild the Flathead I bought for it. Finding a power house that runs now a days for cheep or free is like finding that damn leprechaun at the end of the rainbow with a little pot of gold. You're going to be looking for a long time.

 

Haha! Who would have thought that station wagons would have become cool? Think about all those guys who had to park a mile away from the car hop just so he wouldn't get his ass beat for driving his mom's wagon to the Saturday night cruise back in the day. Now think about that same guy's grandson who is pulling all that ass at the Lone Star Roundup every year when he shows up in his great-grandmother's station wagon. Now that's just funny.

 

I believe Weiand made manifolds for these up to about ten years ago. Check out the dedicated Mopar sites for parts.

They got a second hand factory dual quad anchor on that auction site for $350.


I've always heard these "semi-hemis" were practically bulletproof.

 

our family wagon when I was very little had a poly in it...the later one that I "got to" drive had a 2bbl 383, and you're right about having to park a mile away

 

Jeesh, I bought one of those in the 80's for $50 and sold it for $125.

 

That's a typical brag about several kinds of engine that didn't make enough power to blow themselves up

 

They are great engines but like they said, they are not cheap to rebuild. I am doing one for my 66 Satellite, I can post some pics up later on tonight. And yes you can still find speed parts for them. I got a custom ground cam for it that I can still use the stock torque converter with, Weind intake, those TTI headers posted above and some uniquie vintage Edelbrock finned aluminum valve covers with the vintage script lettering. Let me know if you need any other info or help.

 

For those with a serious interest, just do a basic search for '318 Poly' and spend the rest of the day reading. When you get to any mention of Gary Pavlovich (also here on the board), stop and take notes. Gary has probably forgotten more than the rest of, collectively, have ever actually known about polys...

...search...search...search...

.

 

The first car I learned to drive in 1986 was my mom's 1963 Plymouth Sport Fury. It had a 318 Poly with 2x4 intake. It also had the old Max Wedge Scoop. I loved that car, still one of my favs today. We drove that old girl EVERYWHERE when I was young. The engine never let us down and was still running when the torsion bar mounts rusted thru and she got junked.

 

Of all the car guys I've known over the years, only one was actually into the early 318s (he had one in a '37 Ford coupe) as far as building them as a performance engine goes. This was probably thirty years ago, and one nice side benefit of it was, much like it was for me when I was messing with Corvairs, once he became known for liking them, people began hauling parts of them and even complete engines to his doorstep and GIVING them to him. Maybe not the fastest engines he ever owned, but certainly the cheapest!

 

I just bought a pair of poly heads at a swap meet, and i have a few 392 blocks would they work on a " 92 "?

 

Not likely...the early Chrysler poly is not the same engine as the later 318 poly.

 

There are two iterations of the Poly, the later "A" motor is what is being discussed here, the other is a single rocker shaft poly head on a hemi short block - no interchange.