440 Block Selection

Technical Question and Answer - On topic to 71-74 Plymouth B-bodies only.

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luvmoparz
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440 Block Selection

Post by luvmoparz » Mon Sep 22, 2014 11:59 am

Been awhile since I posted.

Question: I want to build a motor and just put my numbers matching original aside. Since I am building from scratch does it matter the block I choose? Are all blocks the same? Is a motor home block same as the block for an HP motor? Please enlighten me engine gurus.

I am planning on fuel injected setup (the Edelbrock heads, manifold and injected carb is what I am leaning towards). It will be an A/C setup (the wife insists that the car is comfortable), Automatic (727) and stock 8-3/4. Plan on maybe a nitrous for drag runs , mainly just a very solid friendly setup. Just want to be able to take in bare block, have it gone thru and add all parts.
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road chicken
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Re: 440 Block Selection

Post by road chicken » Mon Sep 22, 2014 12:44 pm

From my understanding you will want to avoid the 76-78 blocks as they were thin wall bores and limited to 0.020" over bore. The 67-75s block being the best. I am not sure if there was a preferred year for material composition. However, you should look at the core shift on any block you are considering. 1 quick check will be to look at the cam bore and see how well it is centered in the casting. The second , and the best way, is with a sonic test of each cylinder bore. That will show the wall thickness and evenness of the casting.
Another check on any 440 is to have it magnafluxed to check for cracks in main bearing saddle to cylinder bore area. This isn't a concern ( usually) with the 383/400 blocks. Sometimes you can see them and these are not easily fixed.
I believe the motorhome blocks were the same but the heads were different for better cooling flow. I might be wrong. If it came out of a motor home check the engine mount holes to be sure they are compatible.
You may also want to consider a 400/383 stroker. The 440 blocks are going to be expensive where a 400 stroker will get you a few more cubes and cost about the same if your going to buy the internals separately.
4th generation B bodys- there is no substitute.
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Re: 440 Block Selection

Post by SureGrip » Tue Sep 23, 2014 9:50 pm

440 Source has an excellent page on the various blocks.

http://www.440source.com/blockinfo.htm
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kenny
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Re: 440 Block Selection

Post by kenny » Tue Sep 23, 2014 10:32 pm

While i was looking for the same link posted a few minutes ago by suregrip, http://www.440source.com/blockinfo.htm i am glad you had that also i was starting to think i imagined it i had so much trouble finding it. Furhermore, i agree with road chicken about building a stroker with a 400, they came with the largest factory bore and people sell those a lot faster and cheaper but you can get big displacements and power with those kits.

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Re: 440 Block Selection

Post by moparite » Fri Sep 26, 2014 9:35 am

You may want to read this...
http://www.moparmusclemagazine.com/tech ... ine_build/
You never mentioned what kind of budget you have. This could be the game changer if it's limited.

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road chicken
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Re: 440 Block Selection

Post by road chicken » Fri Sep 26, 2014 4:38 pm

Cool, I guess that takes care of improper tribal knowledge.
4th generation B bodys- there is no substitute.
68 383, Street Demon 750, RPM top end,484/284/108 poo poo cam "-5 spd 4:10 SG, 4whl disk, Helwig Anti-Sway, Poly bushings,Firm Feel Box, HD Linkage, 1" t-bars, 7 leafs Springs

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luvmoparz
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Re: 440 Block Selection

Post by luvmoparz » Sun Sep 28, 2014 12:03 pm

Good info....Thanks guys!! This stuff all basically tells me that I can start with Any 440, including Motor Home ones which are always available locally. I like the idea of the extra cooling ports (figure 8's) as it get pretty hot here in the summer (107 last week). this all gives me a great spring board as my boss of all people has been aching to build a motor, so I will have some help.
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rr6pak
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Re: 440 Block Selection

Post by rr6pak » Sun Sep 28, 2014 2:47 pm

What about a stroked 400?

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luvmoparz
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Re: 440 Block Selection

Post by luvmoparz » Mon Sep 29, 2014 9:17 am

rr6pak wrote:What about a stroked 400?
Yeah, that's on the table too.....hunting a candidate now (be it either a 400 or 440). I read the entire article linked above on the 451 stroker
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Re: 440 Block Selection

Post by rr6pak » Mon Sep 29, 2014 10:58 am

luvmoparz wrote:
rr6pak wrote:What about a stroked 400?
Yeah, that's on the table too.....hunting a candidate now (be it either a 400 or 440). I read the entire article linked above on the 451 stroker

I can provide the "DNA" of my build along with the dyno test on what I did to my engine if interested. :D

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