Mopar 400 block 8 sleeves

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At this point its all in pieces and at machine shop. Will have cylinder wall thickness numbers on Monday and we will go from there.
It will be perfectly fine as long as the work is done properly. Just look at an aluminum block. They all have 8 sleeve’s. Kim

Yes but they were designed for that purpose. Cast Iron block is not... OK you guys are right! It will be perfect! :)
 
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I talked to machine shop today and they will most likely want to use 3/32" thick sleeves. They were also thinking about 5/64" thick ones. They showed me some diesel blocks with these thin ones and said its factory spec for Perkins for example...
 
I think that’s the size used forever. I hated the idea of sleeves. Took a 340 to the machine shop. A wrist pin came out and scored the bore. This was 1975 or 76. It’s still in there. In the late 90s had a butt sleeve put in a 440. Still fine. Kim
 
I hope you are right, some people disagree thats why I'm worried.


I've set so many sleeves it's not funny. Some on brand new blocks.

Done correctly the sleeve is at the very worst as good as what the OE casting was.

If you use a ductile iron or better sleeve it will be far better than OE.
 
I talked to machine shop today and they will most likely want to use 3/32" thick sleeves. They were also thinking about 5/64" thick ones. They showed me some diesel blocks with these thin ones and said its factory spec for Perkins for example...


I like the 3/32 if you can fit them in there. And I like to look at the entire listing of sleeves and find a sleeve with the OD I want and the smallest ID I can use so I don't machine away the sleeve to get the bore size I want.

For example, if I was doing a SBC, I'd look at the 3/32 wall sleeves in the length I want and then I pick the ID so I only take .020 or so out.

Some guys just look up the sleeve by application and I don't do that. I try and leave as much of the sleeve in there as I can.
 
More thoughts as I'm sitting here. Don't rule out an .125 wall sleeve. If you can get the OD in there, I like an 1/8th wall when I can.
 
More thoughts as I'm sitting here. Don't rule out an .125 wall sleeve. If you can get the OD in there, I like an 1/8th wall when I can.
What is minimal cylinder wall thickness acceptable before sleeve gets installed? What is too thin?
 
What is minimal cylinder wall thickness acceptable before sleeve gets installed? What is too thin?


If you can keep .080 wall in the block and keep the sleeve at .080 at finish size that fine.

Look at an aluminum block and how sleeves are set in those. It is nearly impossible to keep a sleeve straight and round in an aluminum block. The block itself moves all over the place.

Even with the very best sleeves I could find, even correcting the bores before setting the sleeves, they don't stay round.

So as long as you use a quality sleeve and keep its wall thickness as thick as you can, you can get pretty thin on the OE cylinder.

And, before I forget, you need .0007-.0009 press on the sleeves. Any more than that and it just moves things around. If the sleeve is set as far down the hole as possible so it sits on a square ledge around 100% of its diameter, it will never come out

Some guys love flanged sleeves. I don't use them unless there is no other way. The flange weakens the deck a bunch and then you have the flanges overlapping. PITA for zero gain.
 
If you can keep .080 wall in the block and keep the sleeve at .080 at finish size that fine.

Look at an aluminum block and how sleeves are set in those. It is nearly impossible to keep a sleeve straight and round in an aluminum block. The block itself moves all over the place.

Even with the very best sleeves I could find, even correcting the bores before setting the sleeves, they don't stay round.

So as long as you use a quality sleeve and keep its wall thickness as thick as you can, you can get pretty thin on the OE cylinder.

And, before I forget, you need .0007-.0009 press on the sleeves. Any more than that and it just moves things around. If the sleeve is set as far down the hole as possible so it sits on a square ledge around 100% of its diameter, it will never come out

Some guys love flanged sleeves. I don't use them unless there is no other way. The flange weakens the deck a bunch and then you have the flanges overlapping. PITA for zero gain.

They excluded flanged sleeve right after looking at block deck.
 
So here are sonic check results. I put the lowest values here.
There is no way to have sleeve and .080" of original block wall left.

Machine shop wants to bore it to see if .040 over will clean the bores.

Seems that I'm out of luck with this one.
Any advice?

Its going to be high hp setup with Indy top end and 470 stroker kit thats why all these questions and doubts on my side.

400sonic.jpeg
 
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They want to try 0.040” because the bores are reverse barrel shaped.
 
How much block filler do I need to half fill it? ;-)
 
IDK, unless this is going to be over 650 HP or blown or something I'd use a 3/32 wall sleeve and run it.

The thin areas are mostly on the non thrust sides by your diagram.
 
IDK, unless this is going to be over 650 HP or blown or something I'd use a 3/32 wall sleeve and run it.

The thin areas are mostly on the non thrust sides by your diagram.

I was 640 before tear down, now it should be 700+ easy.
Thin areas are also on the very bottom where half fill will help so I am going for it if bores clean. We will see how it turns out. It will be .108-.110 wall if it cleans.
Will know very soon and report whats next.

Also talked to ICON about their piston to wall cearance.
Piston advertised for 4.382" hole is really 4.3775" size. They recommend piston to wall clearance between 0.0045" and 0.0065". Maximum hole size is 4.384".
 
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OK so it turned out that bores were not square with crank which helped the situation a bit. The block cleaned at 4.378" before hone.

I'm now back at the idea of taking my 4.375" pistons and "growing" them with ceramic coat. Normal layer they apply is up to .006 thick in diameter and they do .003-.004" fit.
The block should be 4.380" honed easily.

Fianally something positive.

400.jpeg
 
Turned out that 4.381 is as small as it can be. I confirmed with line2line about coating. Will ship pistons to them this week...
I will post updates in this thread till I finish this build.
 
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