Polyspheric Hemi???

In the order I'm seeing, the top engine with RedRam on the valve cover isn't a 277, might be a 270 though.

 

yeah it was a couple years back, that coulda been it.

 

Speaking of:
http://www.1962to1965mopar.ornocar.com/poly318_1.html

Who do you think did the first interchange on the 'net?

~Jason

 

From what i was told when i had one in my fury is its an all day affair to adjust the valves on these motors. And they are real heavy.

 

Per: http://www.bbc.co.uk/dna/h2g2/A1149266

"The main advantage of the Poly over the Hemi is weight. It has more horsepower than the famous 318LA, and per cubic inch its power is comparable to that of the Hemi - yet it is much lighter, making its power more noticeable."

A 318 Poly, post-1962 (that have the same bolt pattern on the back as an LA motor) is 608 lbs, FYI.

~Jason

 

SORRY i dont have any idea where i read about the poly guys over seas,,,

that pic of the gold/chromed poly looks killer,,,,

QUESTION,, maybe i was dreaming,,but i thought i read years back,,that one of the hemi motors intakes interchanged with the 318 poly ???

i is this true?? or a pipe dream,, was the 318 poly intake boklt pattern different from all others??,, just some thing that has bothered me for a long time,,, i know i read it some where.....

 

Of all the polys, the 318 is the most common, and is about the only one you can't do a Hemi head conversion with. Sorry, man.

And yes, the 318 Poly (and the 277 & 301, 303 as well) intakes are totally different: no valley cover. They're all one-piece.

~Jason

 

they make performance parts for them though, so why would you need to.

 

The Dodge hemi & poly (241, 259, 270; 315, 325) intakes interchange, but only in the same deck height.
The Chrysler (301, 331, 354) intakes interchange but I'm not sure the port sizes match - the hemi is probably larger.

 

panic,,Show me a 259 Dodge Hemi..Also the log manifolds will fit them all..
Duane.

 

**** i dunno.... dan quayle?........

 

It was, in fact, Dan Quayle, tool of the devil.

 

The Plymouth Polys can not be made into a Hemi. The most common coversions are the 331 and 354 Chrysler Polys, which can be made easily into the appropriate 331 or 354 Chrysler Hemi engine.

In case some of you Mopar noobs were not aware: Chrysler, Dodge and DeSoto all had their OWN Hemis. Virtually NO parts interchange between makes. Plymouth NEVER had an early Hemi of their own, and you could not get a Hemi in an '50s Plymouth, period.

The Poly 318 A-engine has limited parts interchangeability with the later LA small blocks, such as distributor, timing set, pulleys, water pump, crank, and rods. Block, heads and intake and exhaust manifolds do NOT swap between the A and the LA engines. They will bolt up to any small-block bellhousing, from '62 on, IIRC.

 

Except the 259 '55 to '57 I think were the same as Dodge polys. And as such Dodge hemi heads will fit a '55 and '56. Maybe a '57. Maybe not.

 

As I previously posted, we have a running example of such a conversion; the motor clearly has Hemi heads, but the number on the top front of the valley pan comes up as Plymouth car, '55 if I remember correctly.

 

Plymouth 241,259,270 & DeSoto 325 Polys were all built on Dodge Hemi blocks & can be converted to Hemi.

 

Here's a chart:

http://www.thehemi.com/engines.php

~Jason

 

man, this is why i stay away from them cars.... gives me a headache! lol and this is just the motor! the brakes...... a whole other issue! =P

 

& most of this is on ScooterMcRad's Hemi Tech Index.

 

Touche', my friend!

~Jason

 

Or the joy of reverse-thread lugs?

~Jason

 

Hey, Pontiacs had those in the early '60s, as did others. My old '62 Tempest LeMans ragtop had 'em!

 

Not the headache that Ford engines are!!!

 

The brakes are the same as what all the cool kids want to run on their hot rods. The motors are the easiest part. If you want an early Hemi just buy a Hemi. It would be a lot cheaper and easier that converting a Poly. Or just get a tall deck Poly and have 20 more horses than a low deck Hemi.

 

yeah... i was a 18 year old kid when i first ran into that. sat there hankin on that lug cross just about busted the vains on my head or something.... finally took it to the tire shop and was like "i dont know how to get the ****in rims off, youre just gonna have to do it" (was going to bring them the wheels to put the tires on) some 80 year old man walks out and is like "what year is that plymouth?" and im like "49" and hes like "ohhhhh its reverse thread!"

DOH!!!!! i love getting schooled

 

no they really arent. they have 2 wheel cylinders per wheel. sometimes not.. on the same car.... mid year changes, different masters ECT ECT.... trust me, its nothing like ford! ford is like this... 1939-19** fits all the same. lol **** even ****in lincoln and F1 brakes fit on 30s spindles... try that with friggin Chrysler... not happenin.

 

I have a '55 Plymouth Poly 260 motor that I have been trying to sell. As I understand it, it is the same block as the 241 and 270 Dodge HEMI motors. I have been told that the 241 heads work best of you are looking to convert. From what I have seen the 3x2 Offy intake I have for it will work with the HEMI heads as well but no comfirmation on that as of yet.

 

The Plymouth 259 uses the same manifold as the 241-270 Dodge. The heads and stuff can be switched to get a hemi. The first engine posted looks like a 325 to me. It can be converted but you must use D-500(315) or KD-500(325) heads . A bit hard to find.

 

The best heads to use are 315 or 325 on the Dodge blocks, 270 heads less so. 241 can be used even on a 325 but best on the 241 because of valve/port size. sealing @ the top of 241 heads is marginal on 315/325.

 

well great info here,, as to my question,, i think was misunderstood,,,i swear i read in a mopar magazine that some early hemi intake would fit a 318 poly,,, i have seen a few 318 polys with 3 duces,,and thats what the article was about,,,but you know those magazines,,im sure it was incorrect,,

as for the interchangeabilty of the dodge hemi to dodge hemi,,i didnt know the heads were different,,logiclly you would think they wouldnt because or cubic inch,,,

while we are talking dodge hemi heads,,will the tall deck 315 / 325 heads fit the 241 / 270 ?? just so i know im sure ill be needing heads,,mine are probably cracked,,but thats on a different topic,,,thanks alll this is a kool site,,