Any concerns going .040 over on a 5.7?

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b5cuda

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Hello everyone, my 2013 5.7 block needed bored .040 to clean it up (sat too long with moisture before I got it). Basically got the block for free due to its condition. I'm assuming that if they make pistons that size the block is able to handle that bore. Any concerns with going that big?
 
I've seen a build story where they went to 4.020...

If you look down the water jackets on a 5.7 they look like they have a partial fill in the block but it's cast iron not concrete. Strong design.
 
Most Gen 3 Hemi blocks can only be bored 010-020 only so it’s sleeve it or replace it. I don’t think anyone makes any pistons over 020
 
Thanks for the replies!
.030 and .040 pistons are available.
 
Well, just because someone makes pistons that size, "doesn't mean you should". I have factory/dealer tech literature (somewhere) from when the 5.7 and 6.1 engines were the only players at that point, stating no more than .020 on one and .030 on the other. It might have been .020 on the 6.1 and .030 on the 5.7. IMO, these new gen blocks are not designed to be rebuilt but about once. 440 blocks in the day could go up to about .060 over, but not these gen 3s
 
Hello everyone, my 2013 5.7 block needed bored .040 to clean it up (sat too long with moisture before I got it). Basically got the block for free due to its condition. I'm assuming that if they make pistons that size the block is able to handle that bore. Any concerns with going that big?
If its going around that over boring is limited..I'd look at casting number on such regard and calling some reputable builders who specialize IF I couldn't just have them sonic tested.
 
There have been 5.7 builds done by reputable shops where they have a large overbore. ALL other things like piston availabiltiy put aside, they have one thing in common. They were SONIC CHECKED before boring.
 
Thanks for the input, I'm not an engine builder so learning as I go. I saw a price for sonic testing listed at $160 for a V8 block, does that sound about right? I also still have the set of used standard bore pistons. If I bought another standard bore used block, should the pistons and block match up or would some machining be required?
 
You would definitely have to measure to be sure. With that said, I have done it. But, not without measuring piston and bores first.
 
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