318 Poly A engine in a 67 Cuda

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Dmopower

Dmopower

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I have seen some peoples cars that have done this swap but have not been able to talk with anyone who has personal experience in this swap. I'm looking for information on this swaps possible issues. I have measured 64 B body's and they are 1" wider inside fender to inside fender. The 64 B body has about 7/8" between the exhaust manifold and the power steering sector. I have not seen any other issues but would love to hear from someone who's done this or has information about this swaps issues to be worked through. Pic was found on this site and is just for attention. ;)

Thanks.

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Don't think really worth it, main difference is the heads and LA has better options, if I had to squeeze something in it would be a big block :) but each to their own.
 
273 said:
Here's a 550 hp 402 poly

Vintage Mopar Power! 550HP Chrysler Poly 318 V8 on the Dyno
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I have been researching these engines and it looks like I can build one of these into a 412 or bigger engine. The heads can be ported to near tricked J heads and further on the exhaust side. The block has nearly solid main webs and is not limited to 500-600 safe hp like the 340-360 is. Extra nickel in the cast making them stronger pound for pound. I can build a 412 to 450 plus and throw a torque storm on it and make more power than an La engine bottom end will handle. Then there is the being different cool factor. I just need some details on the fit.

I also like the idea if paying an American machinist to do my head work rather than spend it on alum heads made somewhere else.
 
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Dmopower said:
I have been researching these engines and it looks like I can build one of these into a 412 or bigger engine. The heads can be ported to near tricked J heads and further on the exhaust side. The block has nearly solid main webs and is not limited to 500-600 safe hp like the 340-360 is. Extra nickel in the cast making them stronger pound for pound. I can build a 412 to 450 plus and throw a torque storm on it and make more power than an La engine bottom end will handle. Then there is the being different cool factor. I just need some details on the fit.
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If you do take pic's keep us informed be interesting. Wonder why people don't use these blocks
as a cheap race block for LA builds?
 
273 said:
If you do take pic's keep us informed be interesting. Wonder why people don't use these blocks
as a cheap race block for LA builds?
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There are issues lining up water jacket ports to la heads and the block head pins need moved. I think it can be done but I don't know...yet. I will post a thread to follow if I find the poly fits my 67 Cuda.
 
Probably need to make your own headers, other than that should be a somewhat a bolt in.
 
273 said:
Probably need to make your own headers, other than that should be a somewhat a bolt in.
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The exhaust appears to be my only issue. I did some research and found that TTI uses the same part number for 62-66 B body small block headers as they do for 67 up A body small blocks. TTI makes poly headers for a 62-66 B body. And the 62-74 B body LB engine headers can be the same as 67 A body LB engine headers. So there is a chance.
 
They probably spent the extra to make sure the LA and RB fit both so they make one product, might of not cared with the poly since there's little call for A Body application, but might be lucky or need a bit of modification. Concur with giving them a call.
 
The poly has the engine mount ears in the same place as an LA.
Let me rephrase that the LA has the engine mount ears in the same location as the A poly Motors. Because the polys came first. And the LA's copied them. If you magnaflux a 318 poly you should find you can bore it to a 340 bore size. Throw a 4-in crank in there and you should have about a 416? Or bore it to 4.040 and make it a 340 poly. As for putting La heads on a poly block it can be done you have to block those two big holes in the water Passage on the top of the block.
As for headers I have not tried it although I have a set of them here but I was told the fox body 302 headers can be adapted to the poly head. As I said I don't know if this is true.
 
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Jadaharabi said:
The poly has the engine mount ears in the same place as an LA.
Let me rephrase that the LA has the engine mount ears in the same location as the L poly Motors. Because the polys came first. And the LA's copied them. If you magnaflux a 318 poly you should find you can bore it to a 340 bore size. Throw a 4-in crank in there and you should have about a 416? As for putting La heads on a poly block it can be done you have to block those two big holes in the water Passage on the top of the block.
As for headers I have not tried it although I have a set of them here but I was told the fox body 302 headers can be adapted to the poly head. As I said I don't know if this is true.
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I see that the engine mounts from my 273 will bolt right up. I measured a car and my power brake booster will clear the valve cover although it may have to be removed to remove the valve cover. I'm looking at a 4.1" crank and a 4.04 bore would be awesome. I want to stick to the poly heads if I can get them to fit. What are you putting a poly in?
 
I am not a Poly expert, but I wonder what the advantage could possibly be to install a Poly in the Cuda. The LA seems to be a much better choice to me.
 
Dmopower said:
I see that the engine mounts from my 273 will bolt right up. I measured a car and my power brake booster will clear the valve cover although it may have to be removed to remove the valve cover. I'm looking at a 4.1" crank and a 4.04 bore would be awesome. I want to stick to the poly heads if I can get them to fit. What are you putting a poly in?
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Is your car running and driving right now? If not pop off the drivers heads and slap on a poly and see what your dealing with.
 
We have a member here who stuffed a Chrysler 354 Hemi into a 65 Valiant. If that fits in an early A, then a 318 Poly will surely fit in a 67.
 
harrisonm said:
I am not a Poly expert, but I wonder what the advantage could possibly be to install a Poly in the Cuda. The LA seems to be a much better choice to me.
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The poly is a torque animal. The individual intake an exhaust ports just work. I think most of them came from the factory with the solid lifter cam also.
My dad absolutely loved the 318 poly. He always said it was the best motor Chrysler ever made. He was not into performance he was into reliability.
I think if you look at the main webbing of the block you will see where it has holes between each section for windage control.
 
273 said:
Is your car running and driving right now? If not pop off the drivers heads and slap on a poly and see what your dealing with.
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My car is a running car and I don't want to take it down just yet. When the guy is ready to put my frame connecters on and do the tunnel work for the A-500 trans crossmember I will fit a poly in. But that could be spring. Figured if I knew for sure from someone that's done it I could get started on the build. But that's a great idea.
 
Jadaharabi said:
The poly is a torque animal.
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This is in a 64 Dodge Station Wagon. Stroked and poked to 390 CI.
I drove this car,if you didn't know you would swear it was a 440 under the hood.
No brake race, just floor it and it would smoke the tires till you let off. 3.23 sure grip.
I was very impressed.
Just food for thought,, The same guy put a poly in his mom's 76 Cordoba back in the 80's.

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IfItsGotWheels said:
I suggest you contact TTI & ask them about fitment. I'd be surprised if they don't know.
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I called and talked to TTI today. They did not think their headers will fit the A body engine. They also said if I buy a set to try they are mine no matter how much damage if any. I understand but didn't really care for the guys tone.

He did give me the name of the guy who they began to make the poly headers for to see if he had researched the possible swap. He was not encouraging at all. He would be shocked if they fit. FYI.
 
Dmopower said:
I called and talked to TTI today. They did not think their headers will fit the A body engine. They also said if I buy a set to try they are mine no matter how much damage if any. I understand but didn't really care for the guys tone.

He did give me the name of the guy who they began to make the poly headers for to see if he had researched the possible swap. He was not encouraging at all. He would be shocked if they fit. FYI.
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Expensive gamble, depending on your skill set might be better off start from scratch.
 
273 said:
Expensive gamble, depending on your skill set might be better off start from scratch.
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Another guy suggested fox bodys are close. I'm going to order some exhaust manifold gaskets from this build and see how close they are. There may be a chance of only modifying at the engine with custom flange. 75 bucks on ebay for the header flange.
 
Have you looked up Bruce Toth or Gary Pavlovich on facebook? They do poly builds. I think Bruce Toth makes adapter plates to mount 3rd gen hemi manifolds to the poly heads
 
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