decking a 383 block

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Pippen

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I have been reading a lot about people decking the block to bring the compersion up. wouldn't plaining the heads do almost the same thing for less money?
 
I have been reading a lot about people decking the block to bring the compersion up. wouldn't plaining the heads do almost the same thing for less money?
It depends on what pistons you plan on running, I guess. If I was running something that could achieve zero deck height, for some quench, for example, I would deck the block to get there. I would not just arbitrarily deck the block to gain compression. That's better achieved with a piston or head swap, IMO. So for quench, yes, deck the block. For extra compression, there are better ways. Lastly, it's a good idea to deck Chrysler blocks anyway because they were routinely way too tall and crooked, so there's your main reason for decking......if all that made sense. LOL
 
Decking a block is not to achieve more compression, that is done with the proper pistons. The purpose of decking is to "square" the block, improving the gasket surface and insuring it is parallel to the crank making each cylinder more even. Decking a "B" block may erase away the number pad.
 
Well the above statement is true, but it doesn't fully cover the subject exactly. You can deck a block and I have decked dozens of blocks to get the compression up. It's all about removal of volume to gain compression. Decking the block .060" removes a lot of CC's compared to deck a head .060". You can use the free compression calculator at Summit Racing to play around with the number to see the changes you can gain. Just remember you need to make sure the head bolts don't bottom out, and if they do you can buy hardened head bolt washers from ARP and you'll need shorter pushrods. I usually deck the block .100" and use the ARP washers when I do one.

You do not have to mill the intake and lowering the deck raises the intake up on the head surface (very good thing) allowing for the roof of the intake port to be high ported and matched.


Tom
 
There's a lot of truth to what you all say. Their are alot of ways to achieve this. However IMO. respectfully. Your block first needs to be squared up. All or most of all the measurements you do will be based on your block being square.
 
I took .060 off of my trickflows to go from 11.6 to 12.8, that was a lot of time 78 CC's to 65 CC's .
My block was decked true and my flat top pistons ended up .011 out of the deck.
On a stock stroke 383 there's a few pistons that will get you close to top dead center.
Deck it square.
Street car, race car, in between? That will steer you where you want.
 
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