318 polyspherical

[the reverend muddy grimes]

I've been toying with the idea of a different truck. I found one I like quite a bit but know very little about, It's a 1959 Dodge short wide with a 318. According to the research I've done, it came stock with 200hp. people are getting more than double that with some work. Anyone know anything about the poly block that is useful?

 

[BlueNorther]

here's a very complete run-down of that motor:

http://www.allpar.com/mopar/a-engines.html

the A block was the design inspiration for the later LA blocks (273-318-340-360)
but non of the parts interchange.

Hot Rod parts are few and far between (spelled EXPENSIVE)

they do share the same bellhousing bolt pattern, so modern Mopar trans will mount up.

 

[Blue Eyed Devil]

The Poly engines are an animal all their own. They have quite a few different versions depending on when they were built. The link BlueNorther provided is a good read and starting point, but some of the other statements were incorrect. Depending on what series Poly you are working with, from some to quite a few parts can interchange with a LA series engine. Also, not all of the Polys have the later bell housing bolt pattern, so matching transmissions isn't as easy as it sounds. I have had a Poly-powered '58 Belvedere for quite a few years now so I am pretty well schooled on the Plymouth variety. The Dodge not as much, but enough to be familiar. They can produce some respectable numbers with work, but be prepared for sticker shock as with any old engine. However, in stock form they are rock solid performers and capable of most anything you need to do. My Plymouth just turned 100k on the original engine and it is still going strong. Just did a 950 mile round trip in it last month at highway speeds plus and she never even stuttered. I am a believer...

 

[wayfarer]

There are two distinct versions of the 'A' series engines (Poly).
1956-1961 and 1962-1966 (1967 in Canada)
The 56-61 block and crank flange have the same pattern as the /EarlyHemi engines. 62-66 are the same as all the rest of the 318-340-360 blocks/cranks.
The easy way to OD an engine is to see if the crank is 8-bolt (early) or 6-bolts (late).
Plenty of parts interchange between the two series.