Uh-oh! New engine time

Neal Zimmerman

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Well a few days ago I posted about my sad and sick poly 318. I think it's toast. Minimal oil pressure, cold compression gauge test wont even register unless you inject a bunch of oil, timing chain is stretched ( 13-14 crank degrees till rotor movement), and nasty sludge. Game over.
So here's my idea-
I have a good original bore 318 short block (1972 casting) in my shop I have been cussing at for 20 years.
And I looked through all my crap today and I have everything needed to swap the LA318 in for the old dead poly. Everything! Even headers and/or some 340 exhaust manifolds. Even some 273 solid rockers if I wanted a solid cam. And several 318 aftermarket aluminum intakes (single and dual plane)
BUT what I don't have is the heads. Not sure what happened to them. But I do have some 1967 273 heads ,and I need to run the numbers, but I am sure they are closed chambered and no they don't have the funky intake manifold bolt hole situation.
My question is, that there's a difference in bore size between a 273 (3.63) and a 318(3.910), so will that cause issues? I have never tried using SMALLER heads on an
engine, and I really hate cobbling together junk, but its either that or not drive the car this year.
My buddy can bore the block and get me the engine kit pretty cheap, and I will bolt it together.
But it's that disparity in bore sizes that could be my undoing. Will it work?
Anybody here in Oregon with some 318 heads for sale?
 

Kern Dog

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I have a nice set of the '302 swirl port 318 heads....Rebuilt and ready.
I'm in Northern CA though.
These are closed chamber and used on the roller cammed 318 LA engines. They came from an '87 Chrysler Fifth Avenue 318.
 

bm02tj

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I put a set of 273 on an 1981 360
We put hard seats and the 360 valves for a motor on propane
worked well
 

Neal Zimmerman

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I have a nice set of the '302 swirl port 318 heads....Rebuilt and ready.
I'm in Northern CA though.
These are closed chamber and used on the roller cammed 318 LA engines. They came from an '87 Chrysler Fifth Avenue 318.
 

Dave6T4

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I think Indy Cylinder Heads sells rebuilt heads for about $500.00 per pair.
 

Kern Dog

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I'm afraid to ask but how much do you want?
They cost $300 to be rebuilt. I'd take that but shipping will be pricy!
If you know of a cheaper way to go, send me a PM.
 

Big Bad Dad

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I am trying to remember, but not sure... I "think" I have heard that the poly transmission bell housing has one bolt in the pattern that is different when bolting to a poly block VS an LA block. Anybody else know anything about this?
 

Dave6T4

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I am trying to remember, but not sure... I "think" I have heard that the poly transmission bell housing has one bolt in the pattern that is different when bolting to a poly block VS an LA block. Anybody else know anything about this?
They are the same. I think that " one bolt different" thing applies to the new Hemi.
 

Darter6

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I have heard that the poly transmission bell housing has one bolt in the pattern that is different when bolting to a poly block VS an LA block. Anybody else know anything about this?
Heard that too.
 

Big Bad Dad

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They are the same. I think that " one bolt different" thing applies to the new Hemi.
No, my memories are from way before there was a new hemi. I was pretty active with these old mopars back in the 1980s. We were thinking of doing a 318 poly to LA swap, but it never happened..
 

beanhead

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Neal keep an eye on FABO too, or join up and post a WTB ad. They loves 'em some 318 over there..
 
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