Poly Eng Knowledge Needed

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Murray

Murray

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For some reason I find myself fascinated w/ the old poly motors. Am interested in any input about building one as a street rod. I understand that performance potential is limited, but would like to explore available intakes, ignition, v/covers and headers. What is available? Can I build a 4-sp or auto? This might sound crazy but would appreciate some input. Thanks.
 
Which poly are you interested in? There are 2 distinctly different poly engine families
 
Not crazy at all, the second-gen polys were pretty strong performers in their day, especially in the low to mid range... Toth Performance is the go-to guy lately on poly engine builds and parts.
 
watching because I recently purchased a 65 318 Poly. Engine Masters has had a few articles on them...more toward the high end builds. Chrysler Power has 4-bbl manifolds cast up, they may be available again. Ignition is same as a regular small block, as is oil pumps,pans,timing sets. Later models,up to 66,use same transmissions as LA engine. I believe they are neutral balance so a 340 10.5" flywheel would fit. Will dig that and the scattershield out one of these days to verify. Mine came from an automatic car but the crank is drilled for a pilot bushing. Have other thoughts about intakes as far as adapting other brands. Good luck! Yours will probably be done way before mine!
 
Quite a few Polys being built and dyno'd. Big numbers out of those if done right. Parts are a bit spendy though. Poly Super Pac is a group on Facebook and they are part of the Chrysler Power magazine. Poly Super Pac The heads are quite efficient and you can stroke on to 390 cubes with LA parts.

Poly



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Murray said:
For some reason I find myself fascinated w/ the old poly motors. Am interested in any input about building one as a street rod. I understand that performance potential is limited, but would like to explore available intakes, ignition, v/covers and headers. What is available? Can I build a 4-sp or auto? This might sound crazy but would appreciate some input. Thanks.
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Intakes are limited to basically a Weiland aftermarket one for 600+ or a factory 4 barrel, 6 pack or , dual quad, all of which can run from 350-900.

the poly heads will out perform any LA head, stock for stock even more so with porting and polishing.
Headers are essentially limited to TTIs, or you can custom modify a set from a Mustang GT or 351 to fit.

you can also modify an LS intake to fit as well, both are easy to do.

cams can be custom ground for under 200.

I’ll get into more specifics in a later post. Busy at the moment but gives you a few things to think over
 
Professor Fate said:
Not crazy at all, the second-gen polys were pretty strong performers in their day, especially in the low to mid range... Toth Performance is the go-to guy lately on poly engine builds and parts.
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Bruce Toth is a great resource. Gary Pavlovich is the ultimate poly guru. Both guys know those things inside and out.
 
Great engines. Just intake and exhaust up-grades make the world of difference.
Early 60's poly's give you 9 to 1 compression and full floating piston pins like the 340. Head exhaust ports are spaced like the Hemi. Some say that is better than the exhaust ports that are next to each other.Just a few photos
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Photo of a 318 stroked to 390 with Toth performance parts.
This thing can hold it's own to many big block cars.
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2nd best looking engine next the Hemi, i want one super bad! I want to get one when we get a D100 for the wife.
 
I have a friend here in Maryland with a stroked Poly, with the intake similar to post #8. Big, flat torque curve. Loads of potential in Poly's. Back issues of Chrysler Power magazine in the last 4-5 yrs. can be a good source of info. the "new" intake is NOT cheap, but worth it from what I saw on the dyno.

Four Barrel ‘Wind Tunnel’ Dual Plane Manifold
 
This gentleman built a stroker poly for a customer sounded pretty mean when he fired it up for me on the engine stand,He is currently building a total custom poly stroker for the guy whos suppose to be the poly guru..Hekimianracing.com
 
There are 3 different poly engine families. The most common is the A engine type, first seen in the 1956 Plymouth. This one was produced until 1966 or so when the LA engine replaced it.... sharing many parts.

The other two types were based on Chrysler and dodge hemi v8 engines.
 
This is the poly for my Satellite. I have an older regrind in mine. They can be made to look pretty for sure. The wind tunnel is the only new intake available. Otherwise the Weiand 7503, and factory single and dual four barrels. Gary and Bruce really know there stuff.
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after a million Mopar shows and drags, it's great to see something out of the ordinary, especially in a street rod. I encourage it !!!
 
The 4" stroker LA crank is a direct bolt in for the 2nd generation poly engines.
 
The part I left out of my earlier post - when they ran Bill's stroker Poly on the dyno, they had one of the old Offy 4 bbl intakes on hand. A quick swap and pull showed that the raised runner was better everywhere, even below 2500 rpm. Sadly, no printout of that pull.
 
Demonic said:
The part I left out of my earlier post - when they ran Bill's stroker Poly on the dyno, they had one of the old Offy 4 bbl intakes on hand. A quick swap and pull showed that the raised runner was better everywhere, even below 2500 rpm. Sadly, no printout of that pull.
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THose new manifold reminds me of a Air Gap. They look pretty efficient.
 
Mine ain’t purty but it’s still kind of cool looking

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