318 Poly head motor
- Thread starter nitronut
- Start date
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dano
Evil Handy Man
The heads have Poly-spherical chambers. It is considered an "A" engine and shares somethings with the "LA" engines. The valve cover will have 4 bolts in the center of the cover to hold it on.
Those poly engines were good engines.
perfacar
Well-Known Member
poly 318, has bigger valves, cam is different, the crank, rods, timing gears, dist gear, oil pump , pan, timing cover are same as a 318 LA. poly has bigger ports. also, its a solid lifter cam. a four barrel will wake it up.
67Dart273
Well-Known Member
Good luck finding a 4bbl manifold "reasonable."
4spdcuda66
Well-Known Member
X2. The poly is a good engine, just a little tougher to get performance parts for a reasonable price. There are factory 4 and 2X4 manifolds, and Weiand aftermarket 4bbl which is out of production. People who have these think they are gold. The valve cover looks like a saw tooth on the bottom rail due to the canted valve configuration. I have one of these engines in stock 2bbl form on a '67 Fury and has plenty of power and decent mileage. Not a race car by any stretch though.
POLY?
Great people mover engine.
Expensive to build up.
Many possible combo's.
Will accept current stroker cranks, no problem. Pistons on the other hand......
TTI, the only header company, period.
Great people mover engine.
Expensive to build up.
Many possible combo's.
Will accept current stroker cranks, no problem. Pistons on the other hand......
TTI, the only header company, period.
4spdcuda66
Well-Known Member
Can be bored to 4" also. Not sure how well the heads would hold up to that much displacement though.
threewood
Well-Known Member
Love mine, it is a great motor. I was on the fence about building it because performance parts are expensive. But it was original so I did it. 4 bbl intakes go for about $400 - $500. Chrysler Power has a new production 4 bbl in the same price range. TTI headers are about $600 a set. Stock compression pistons are abundant. Anything higher than 9.0 to 1 are custom and about $800. A couple places make cams for them. I have a Schneider Cam in mine and it is plenty lumpy with d 2 1/2" exhaust.
If you want to build it, contact Gary Pavlovich. He is the man to talk to about polys.
If you want to build it, contact Gary Pavlovich. He is the man to talk to about polys.
RPMagoo
Just An Old Motorhead
Clean it up, put a 4 Bbl on it, and a set of duals, and it will be a real nice cruiser --- Talk to Roland at www.chryslerpower.com for options.
goldfish65
Well-Known Member
They'll run forever. My go-to back in the era when a Fury or Belvedere was an affordable used car. 100k+ miles would have scared me away from a Ford or Chevy but not that engine. I never did anything but change the oil, plugs and wires and drive them. Pulled the car up to high speeds very easily. Valve covers gaskets prone to leak.
midnight340
Well-Known Member
Definitely good motors!!
After a sonic check! Just don't say it will when it may not.
The heads, if ported right can do well. Your worry about the heads abilty and the possible displacement are unfounded and assume an improper match up due to a supposed short coming. I guess a lot is what your doing with it. Considering there is enough flow in a set of CNC heads (I had seen once @ FBBO) there is enough for 600HP.
Is that enough head for you?
All I can say is, "Wish I had the cash for that CNC job!"
perfacar
Well-Known Member
I flow tested a poly 318 head, @ 25 " was 158 cfm. owner went home and did some porting on it. mostly raised roof some. little bowl blending, test was 195 cfm @ 25 ". it had stock 1.84 valves, sst would have helped out flow. BTW , only tested to .500 lift, flow was climbing way after that.
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