Poly 318 Short Block
- Thread starter Earlymopar
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medicineman
Active Member
I have a complete and running 318 poly in my 65 D100, 3 on the tree, I will be pulling it out for upgraded power plant soon. Carb to pan and water pump to crank flange.
Earlymopar
Member
Thanks MM. I found one locally about 2 weeks ago. - EM
medicineman
Active Member
great!! best of luck to you. Hey BTW, can you tell me how to remove rocker shafts so I can replace valve seals? I had no luck, so I must be missing something some where. Very different than the LA engines being so simple.
Earlymopar
Member
Yes, they are very different at the heads. There is a small pin that has a kind of "mushroom" head on it that is in the top of one of the rocker shaft supports. From memory, both the driver's side and passenger side pins are in the support that is at the front of the engine. In other words, the rocker shaft support that is the furthest toward the front of the engine is the one that has the pin. These pins need to be pulled straight upward using a small slide hammer. They come out relatively easy. After the pins are out, you need to use a wood dowel and a hammer and drive or push-out the rocker shaft so the rockers will slide off of the shaft. Go slowly and be careful. If your engine is in your truck it may be difficult because you have to allow for enough distance to for the length of the shaft. I have only done this job with the engine out of the truck.
- EM
- EM
medicineman
Active Member
I wonder if shaft will clear the radiator support??? It seems I recall a head bolt too in that forward shaft support, any idea if it is leave alone, loosen or remove that bolt? I'm thinking, not relieving crush on head gasket, I think it would be ok as stout as these engines are??
Earlymopar
Member
You would have to measure the shaft length and then the clearance between the front shaft support and the radiator support to see if you have room. I don't recall removing any head bolts to get the shaft out.
medicineman
Active Member
Thanks Early, I'll give it another go and hope all goes well! Old valve seals are gone, I'm sure brittle, broken seals litter these heads, just trying to slow the oil from pouring down the guides and fowling my plugs, I'll get a notch or two hotter plugs next time too. That will buy me time before upgrading the mill and going 5 speed OD trans. Then it can still be driven as needed, until I'm ready for the changeover.
Earlymopar
Member
You are doing with your engine what I did to mine. My 65' Utiline was a stock slant and 3 speed column shift. I bought a running, well-used Poly for $100 that has 110,000 miles on it. So I cleaned it up, tuned it up, replaced the freeze plugs, replaced valve stem seals, etc. I'm just now putting it in my truck. I have also made my own adapters and have 302-351 Ford headers. I also made a single 4 barrel adapter to fit an offenhauser 3 2-barrel manifold. The last thing I did was adapt a Mustang T-5 -speed to it. I'm planning to change the T-5 to a TKO 500 though because the T-5 even when built to handle decent HP is a bit noisy and can still have breakage problems. I have a 2nd Poly I'm building while I drive the stock engine. Good Luck on yours. - EM
LocuMob
Fluid Technician
How did you do that? Does it still have the 3 pads for the 2bbls?
Earlymopar
Member
LocuMob
Fluid Technician
That's much better than what I've seen when people attempt to modify a multi carb intake. Have you used it yet?
Earlymopar
Member
I have not but don't really expect any issues. I may end up experimenting with some type of shroud over the center carburetor ports to allow each location to draw an even air/fuel amount. I will run this for a year or less and will change to my new poly, new larger valve heads and will change the top of the plenum and add a magnuson supercharger. Nothing crazy in size but it will add another 30% to the 350 HP the new engine will have. So, somewhere in the 475 HP range when all is said and done. - EM
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