how large a bore with a sleeved block?

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whitepunkonnitro said:
Going beyond the factory recommended overbore limit ( generally .060) exponentially reduces rigidity at the deck surface.
Block that are designed for sleeves have their head bolts anchored to the spine of the block and not the deck, directly.
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Just sumpthin' I ran across in my '65 FSM the other day is that they list .040" as max overbore at that time, for both small and big blocks.
 
abdywgn said:
I guess my question was not clear, my wife says I have this problem. what is the largest sleeve that can be put in a small block...after removing the entire bore what while fit? are the head bolt holes the limiting factor or water passages on the deck? it's more of a how large a bore can be put into the block?
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Machining the bore without walls to fit the sleeve would be difficult... If you take out the whole bore that is cast into the block and only have "ribs" left to put a sleeve into would be hard to machine a bore for a sleeve as every time the cutter hit a rib, it would side load the cutter and cause it to be out of round and also may break the cutting insert.... It could distort the center line of the hole/bore and make the bore axis crooked along the length of the stroke....
 
abdywgn said:
I guess my question was not clear, my wife says I have this problem. what is the largest sleeve that can be put in a small block...after removing the entire bore what while fit? are the head bolt holes the limiting factor or water passages on the deck? it's more of a how large a bore can be put into the block?
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I/we ran into this when fitting a small block Chevy head assembly onto a stovebolt six cylinder. The problem is the head bolt holes are anchored by the deck and the thick areas around the bores. So you would be limited more by the effects of loss of structure on the sealing ability because of the head attaching methods than the bore size. The reason I mention Darton is they specialize in exactly this. Their conversions remove the deck surface and head bolt holes and are sealed to the bottom of the bore and each other to prevent leaks. It is a very precise set of operations to fit the sleeves into the blocks. Lesser machines can't give the accuracy they demand. So it's not common sense, it's motivation and ability. If you really wanted to, and can afford it, I'm sure much larger bores could be used. But I'll bet money the cost of the engineering, the sleeves, and the installation work will be much more than a better block and that required machining would cost.
 
moper said:
I/we ran into this when fitting a small block Chevy head assembly onto a stovebolt six cylinder. The problem is the head bolt holes are anchored by the deck and the thick areas around the bores. So you would be limited more by the effects of loss of structure on the sealing ability because of the head attaching methods than the bore size. The reason I mention Darton is they specialize in exactly this. Their conversions remove the deck surface and head bolt holes and are sealed to the bottom of the bore and each other to prevent leaks. It is a very precise set of operations to fit the sleeves into the blocks. Lesser machines can't give the accuracy they demand. So it's not common sense, it's motivation and ability. If you really wanted to, and can afford it, I'm sure much larger bores could be used. But I'll bet money the cost of the engineering, the sleeves, and the installation work will be much more than a better block and that required machining would cost.
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In other words, save tons of money & time with a race block that can be bore to the desired size.
There is a guy named "Ritter."
 
Here's the thing no one has really touched on. Bore size is NOT the way to add power. It's all about stroke. You will have minimal effect on power output with bore size given the limits of a stock block. Even with a race piece like the Ritter or R3 or whatever, the stroke still out powers bore for power. Every time.
 
RustyRatRod said:
Here's the thing no one has really touched on. Bore size is NOT the way to add power. It's all about stroke. You will have minimal effect on power output with bore size given the limits of a stock block. Even with a race piece like the Ritter or R3 or whatever, the stroke still out powers bore for power. Every time.
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Really? let's not forget that to a point a larger valve in a larger bore block will have better flow than trying to fit that same valve in a smaller bore and notching the block. this question when started was more of a what if than let's do this. and as mentioned, it has beemn done. particle? no, but done.
 
moper said:
The problem is the head bolt holes are anchored by the deck and the thick areas around the bores. So you would be limited more by the effects of loss of structure on the sealing ability because of the head attaching methods than the bore size. The reason I mention Darton is they specialize in exactly this. Their conversions remove the deck surface and head bolt holes and are sealed to the bottom of the bore and each other to prevent leaks.
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Just curious: Does Darton end up with the head bolt threads in the final top surface, or do they use long bolts/studs down to a point low in the block?
 
abdywgn said:
Really? let's not forget that to a point a larger valve in a larger bore block will have better flow than trying to fit that same valve in a smaller bore and notching the block. this question when started was more of a what if than let's do this. and as mentioned, it has beemn done. particle? no, but done.
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You've been given good, common sense answers by some people who've hit water boring blocks. <hand raised>

Yet, you continue to argue as if you want someone to tell you "yeah, it'll work, go for it"".

So yeah, it'll work. Go for it. Bore that mutha ****** till you see daylight.
 
harrisonm said:
Hey, abdywgn, have you run this by a good machine shop yet? That likely will put an end to this.
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no, because it was just an inquiry. as I read it, yes it can be done but is not practical for the everyday Joe. now, if I had a Van Norman 944S, chip and chunks would be flying.
 
abdywgn said:
no, because it was just an inquiry. as I read it, yes it can be done but is not practical for the everyday Joe. now, if I had a Van Norman 944S, chip and chunks would be flying.
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And I'd be right there with you with a truck load of blocks to see "what was what", but the sad reality is, 1) it won't work and 2) it won't work. LOL
 
Nitro Will said:
Just my 0.02 cents. I have a 1976 360 block with a 60 over sleeve. Eveything seems ok.
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My 417 was built from a 77 360 block I had and it sonic tested good. In fact, it could have gone another .030 safely, but that's an extreme rarity. I just "got lucky" as they say.
 
Hey, I got your block bored out. You said you wanted it bored out to the max. :lol:
metal-shavings-in-pile-DMM1JM.jpg
 
harrisonm said:
Hey, abdywgn, have you run this by a good machine shop yet? That likely will put an end to this.
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They (not all machine shops) don’t all have the answers.
I got my answers here.
My shop said, do they make a .060” or .070” bore piston? Then you are okay. That wasn’t good enough for me to gamble my money with.

The machine shop’s experience was not in SBM.
I paid $125 a hole for .060” sleeves.
Those sleeves were my insurance against being too thin or too hot-points I learned here.
I ended up here with a $60 block when all other cores were $500 and $210 for KB-107 .060” pistons. I don’t plan to beat all comers, just a rebuild too soon.
 
abdywgn said:
no, because it was just an inquiry. as I read it, yes it can be done but is not practical for the everyday Joe. now, if I had a Van Norman 944S, chip and chunks would be flying.
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Not to be a downer, but you would need much more than a Van Norman 944s to do the job
 
abdywgn said:
maybe playing with all those blocks,one would finally work!
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Now............here's a thought. Fill that ***** with hard block. Bore it out as far as the bore centers will allow and run it on methanol. No need for a cooling system.
 
Why even mess with a stock block then. Billet would be smarter.
 
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