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toss the poly 318 for 360?

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just picked it up & degreased it, now time to hit the bead blaster & paint!

gonna stick with the poly. i really like these engines.

im thinking of punching the cylinders .030 over, mill the heads down to achieve a 9-9.5:1 comp, some mild head porting/polishing (mostly a port cleanup) a nice midrange camshaft & the aformentioned factory 4bbl intake & edelbrock 600cfm carb.

You guys think 300-320 hp is attainable with this setup? thats all im looking for.
 
Yes. 4 sure. That is a stock engine with bolt on's.
Call highes engines or EGGE for pistons in that ratio. Screw milling the heads if you don't have to.
 
X2. You're already in for pistons with the overbore, don't mill the heads. You can't put the metal back later, and don't want to change the intake port alignment.

That said, your hp. goals seem realistic. Headers?
 
318 poly

Before you toss your semi-hemi 318, check out the last couple of issues of Chrysler Power magazine for some of the potential of this engine. You'll probably stick with it.

great Mag, just joined....certainly going the stroker route. At present I have a 6 pk, cam, tti ehaust, roller rockers, and ele. disb..

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CP mag has lots of articles on 318 polys.......bolt on's, new manifold and cross ram coming, everything you need is for sale again check out Chrylser Power mag............Gary Povlich is a great guy to talk to.

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see article in CP mag. New intake and cross ram coming in spring of 2015...everything one needs to build a screamer
 
For a budget build.... a holley 500 2bbl ( 1/2 a double pumper) and adapter plate and mopar linkage kit use the green holley accelerator cam it's squared on the end.... valve stem seals some valve lapping compound a set of rings and gasket set got me through school for the price of an intake
Before you get stroked and money crazy on pistons and all that that goes with it wait till is really tiared then go through it all I ran holley 500 2bbl on a 360 4sp in a pickup that scared my buddy who had a 73 charger with a 400 auto in it
 
a 318 poly stroker up to 412 ci. pushing 420hp. that's what's I am going for with a Edelbrock p 600 3 deuce manifold on it . 001.jpg004.jpg001.jpg003.jpg
 
I am gonna turbo charge a poly one of these days..my nephew is into drifting and he messes with turbo's all the time, he has been trying to talk me into putting a turbo on one for a couple years and I am seriously thinking on going that route on my 1960 dodge d 100 with the poly and 3 on the tree wouldn't that be cool,,
 
POLY IS COOL. 440'S ARE COMMON. YES THE POLY WAS A "HEAVY" SMALL BLOCK, BUT THEN AGAIN ARE YOU A "BOY" RACER!?? READ UO ON THE GOOD THINGS ABOUT THE POLY AND YOU WILL PROBABLY STAY WITH IT. READ ABOUT THE HEAD PROBLEMS WITH la MOTORS, AND TRY FINDING A DECENT ONE! OR DECENT 440 FOR THAT MATTER.... JUST ME....
 
Build what makes you and your wallet happy. I had the same question for my 66 charger. Rebuild a tired 318 or build a 360. I found a 360 block from a 77 van. Punched it to 365 CI, keith black pistons, edelbrock heads, roller cam, air gap manifold, 600 CFM carb. Makes 410 HP & 440 Tq. Yes, its not the original motor but I like it and thats what counts. Yes i heard opinions from others on what they would do, but its my car and my decesion. Build it, drive it, enjoy it! Its better than everthing else because its a MOPAR!

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I will buy all the 4bbl Poly manifolds you have at $100 each. Where is your Mopar parts time machine?

:violent4:

If you wait and shop, you will find one. I actually found one on Spokane's craigslist for my '64 fury 4-door. Came with a carb for $150. Met the guy at the Jack in the Box at Sprague and Havanna at his earliest convenience... Sold the carb for the $50 later down the road..
 
Let's bring this back from the dead! For future readers of course. Being that I'm in this very situation, trying to decide between an LA or poly, I figured I'd chime in. I've researched both engines and worked with both engines my entire life. I like both engines. However, there are many practical advantages to ditching the poly. One, the lack of an aftermarket, two, the heads do not flow as well as some make it seem. The poly head is plagued by poorly designed exhaust ports. They have excellent intake ports. But the exhaust is really restricted. Which is the exact opposite of the LA 318. The LA has restricted intake ports but really good exhaust ports. Though, magnum heads are better than both. Speaking of exhaust, headers for the poly are only available from tti and are 725 bucks! You could take that 725 and buy headers an intake and a carb or cam for an LA. If you read around online you'll see several articles laying out 400 horse LA 318's built from mostly factory parts. You will not see that with the poly. Ever. So I vote LA. The poly is cool for cruising around and does have potential. But for the money, the LA, and especially the magnum, rocks the polys world. I'd also like to note the hp rating for the poly is usually a gross rating. The newer LA and magnum is net.
 
Yes building a poly costs more than an LA.
They can be made to run.
Several poly gurus around that can do it all for them.
About having a correct era engine for your car maybe.
Just how many LA motors does one guy want to see in Mopars?
Think of it like this, old school rod, first gen hemi or 318?????
 
Let's bring this back from the dead! For future readers of course. Being that I'm in this very situation, trying to decide between an LA or poly, I figured I'd chime in. I've researched both engines and worked with both engines my entire life. I like both engines. However, there are many practical advantages to ditching the poly. One, the lack of an aftermarket, two, the heads do not flow as well as some make it seem. The poly head is plagued by poorly designed exhaust ports. They have excellent intake ports. But the exhaust is really restricted. Which is the exact opposite of the LA 318. The LA has restricted intake ports but really good exhaust ports. Though, magnum heads are better than both. Speaking of exhaust, headers for the poly are only available from tti and are 725 bucks! You could take that 725 and buy headers an intake and a carb or cam for an LA. If you read around online you'll see several articles laying out 400 horse LA 318's built from mostly factory parts. You will not see that with the poly. Ever. So I vote LA. The poly is cool for cruising around and does have potential. But for the money, the LA, and especially the magnum, rocks the polys world. I'd also like to note the hp rating for the poly is usually a gross rating. The newer LA and magnum is net.
You forgot to mention:
  • 318 POLYSHERICAL HEAD DESIGN INCORPORATES A RIGID SHAFT MOUNTED ADJUSTABLE ROCKER ASSEMBLY THAT SURPASSES THE 340/360 FACTORY DESIGN.
  • ONLY DEDICATED RACE ENGINES OR EXPENSIVE AFTERMARKET EQUIPMENT MODIFICATIONS EMPLOY AS STOUT A ROCKER ASSEMBLY.
 
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