318 W block questions

[Uncle Don]

so my 66 belvedere has the 318w block engine...runs excellent aside from a little carb issue..but runs really smooth, has a touch over 57,000 miles on it.
thoughts about putting headers and a good dual exhaust, maybe put a 4bbl intake on it and carb...or extreme put a cam and lifters in it....

any thoughts? who sells parts for these engines? or leave it alone...:grin:

anyone have any specs on this engine? hp ratings? compression?

 

[mguner]

The poly 318 is a super reliable engine but parts are a bit of an issue. The intakes used to be available from Weiand but no more. They show up on E-bay at times but usually go for around $300. There was a factory dual quad available with two WCFB carter carbs. The dual quad 318 was rated at 290 HP. There are also tri power manifolds out there fore these but again very pricey. Here is a link to a poly motor web site with more info for you...
http://www.1962to1965mopar.ornocar.com/poly318.html

 

[vanrj1]

The Weiand's are going for $475 to $510 on ebay. Dual quad intake alone $225 to $400, not cheap to go with a 4bbl on these engines. I am finishing my build and it wasn't cheap. Good Luck!

 

[rolling_Thunder]

You can score a 4bbl intake but it will be expensive... I had a dual quad intake and i sold it for $530.00... i then purchased a weiand single 4bbl for a whopping $60.00 off of craigslist... it was never installed

cams can be ground almost anywhere - you can use a stock LA SB mopar stick but have it ground IEIE instead of IEEI pattern...

 

[Uncle Don]

if i want to buy a electronic distributor, does it have to be specific to the poly 318? or can it be a newer style 318? and what is the "LA" and "A" talk?? im new to these poly motors and just learning...thanks for help.

 

[David]

Here is a site that might give you a little help on the differences between the two http://www.allpar.com/mopar/318.html

 

[rumblefish360]

Racer Brown has been grinding cams for the "A" engine since the 60's and makes many many grinds. Some of the "LA" parts can be used on a "A" engine, but care must be taken when swaping some things or use of a modern tranny with a older Poly engine.

The A is a small block and the LA is a lightened small block.
A engines dispalce 277/301/&318 cubes.

Swapable parts are springs, retainer, locks, pistons, bearings, cranks, rods, oil pump, distributor, oil pump drive, lifters, balancers and flexplates/flywheels. The rear of some of the Poly cranks are slightly different than the "LA" engins in some years so be careful and take note at this area.

Performance parts are pricey, but some are out there, mostly what you'll need to make it run well and hard. Intakes being the costly stuff and hardest to fine, headers by tti are next on the expensive list and the only game in town for headers.

Stroker cranks also fit in since there the same as a "LA" crank, jfyi, food for thought.
I'm told they can be bore out .060 and be OK. (Sonic check it first to be sure!)

 

[rolling_Thunder]

the Poly can be bored to .090" without issue on most blocks -

 

[MprDoc]

TTI has a set of headers for that specific application. . . only ones who make them. I have read that the heads can be made to flow well too AND you can drop a crank from the LA motors in so you can totally stroke them up. I say go for it, hard to be different nowadays!

 

[mrkinger]

Hey uncle Don ,dont know if this is what your looking for ,but i have a 318 poly with a four barrel.It is a cast iron intake ,i think it came from a earlier 361 or a 313 engine .Might be alot cheaper if you can find one.hope this helps

 

[Uncle Don]

will an intake off of a 361 work on a poly 318?

 

[mrkinger]

Im not totally sure but i thinlk it is the 313 that will fit

 

[Furyman1966]

No, a 361 intake wont fit. I just built a poly completely, so I can answer just about any question you have. CamCraft cams did my cam, I have a weiand 4 bbl intake on it now and also have a Weiand 6 pack intake. I would try and find a stock cast iron 4 bbl for a stock motor. Any more questions please ask.
-Paul

 

[Furyman1966]

As for headers yes TTI's are nice but pricey, I bought a set of shorties off ebay from a guy brand new for $150, don't fit as nice as tti's but for the price difference I made them work
-Paul

 

[Uncle Don]

thanks guys for your help...still deciding if i want to upgrade this to electronic and put 4bbl intake, carb and exhaust or just save money and put the new modern hemi in it down the road....not sure...thanks for help though, ive learned alot.

 

[69 Runner]

361 is a big block. Poly is an "A" small block.

 

[MprDoc]

TTI's are pricey but no one who has forked over the denero for a set has regretted it; you get what you pay for.

 

[66 coronet]

I have a 318 poly head in my 66 coronet. I wanted to build on it but the prices for the old poly head stuff is crazy, you can build two big blocks for the price of a poly. I ported my heads had the valves done and milled them .060 and put it back together with the two barrel. reamed out the outlet on the stock exhaust manifolds and put duels on it and it runs great. As long as the old poly is running good i'll leave it alone when its time for major work i'll look at putting a big block or a 360 in it. The 360 and the 5.9 magnum will bolt in and mate up to the stock torqueflite, all thats needed is the flex plate to mate the cast crank to the balanced torque converter. Summit has these for less than a hundred bucks, they aren't in the catalog you have call them.

 

[MprDoc]

The new LA style small block wont bolt to the stock torque flight. Trust me. Did the same thing with my Satellite. The 66 and earlier 727 have a different bolt pattern than the newer one. Its close, and it looks the same but its not. I just put in a 727 from TCI, only ran about 750 and considering my stock tranny was pushing 170 thousand miles anyway

 

[rumblefish360]

Good mention. The flanges on the crank vari a bit on the early years. Polit holes for manuals also not as deep IIRC. The nice things is, a modern "LA" crank will slide right in and worth considering if your doing a total rebuild.