Just out of curiosity what are some pros and cons of a 318 poly block engine. How come i dont see many used in hotrods and customs? is it cuz lack of performance or obsolete parts?
Relatively heavy for it's relatively small displacement and speed parts aren't the easiest thing to find, and a LA (late A) or Magnum 318 would most likely be far more easier and probably cheaper to build to equal power levels. However the head design (canted valve) is currently all the rage in NASCAR (check out the current offerings by all the manufacturers) and if Chrysler hadn't had the Hemi in the 50s, it might have gotten more respect. Just to offer a fair comparison though, when the dual quad 318 was rated 295 HP in a Plymouth Fury, the 283 Chev and 312 Ford were hard pressed to equal it.
I also have a 318 poly... it looks like FE headers fit with slight modifacation... I'm trying to find a cheap 4bbl manifold but its starting to seem like cheap mopar parts is an ox*****... doh... guess i gotta build the ford.. haha I've read that they were stout little motors. all of the LA bottom end stuff is said to fit (except pistons or something...) but the bore spacing is different...
They aren't thin wall castings so they are heavy and also wide. However they are very tough and have forged cranks. They are also common and cheap to acquire. Building them for performance is a challenge. Although they produce lots of torque there hasn't been much in the way of performance parts and development until lately. There is some interest a**** mopar people in exploiting this engines latent potential. You can occasionally find aftermarket intakes for them on e-bay or over at Moparts On the Web.com. Someone was advertising new header flanges for them but I don't remember where I saw that. There are a couple of cam grinders who offer something. Maybe Racer Brown.
Hi choppermatt, Jason aka "Abomination" on here has lots to say about the poly 318's. Check out this link http://www.geocities.com/polyman64/directory.html It lists all sources which he has found for poly parts. I'm a big poly fan with one in a T-bucket which I built in 1962 and currently fitting one in a 32-5W. Both run finned valve covers and Edelbrock tri-powers. Only thing I had problems getting during a re-build was intake valves and that was cos I didn't want to wait to ship some in from the States. They are BIG and heavy, about 30 lbs lighter than a Hemi and when you add a 727 auto they're extra heavy. Won't fit under a 32 hood without some serious bulges- same as a Hemi. swifty
Pretty much the same with any of the obsolete engines here, technology has p***ed them by. That doesn't mean that you can't build one into a good engine, & there won't be many at any non-Mopar specific car shows!They were overshadowed by the big blocks. They are simular enough to the early Hemi that there is a good build chaper on one in Tex Smith's Hemi book.
The only cons I can think of is that they are wide and heavy. They also cost more to rebuild as has been stated. I, personally, love these motors. Listen to one run and you can tell right away that it ain't a small block chevy and it has a helluva lot of torque down low where you need it. Weiand makes a for barrel aluminum intake for them and there are other parts out there, just not as many as for a ford or chevy. good luck
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