FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: dozz302 on March 13, 2023, 02:27:28 PM
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Just wondering if there are any off the shelf pistons for a 428 with a 4.200 bore. Currently has 1 split cylinder but I might resleeve that one hole and short fill and go with it. Block currently has all 8 cylinders sleeved and is home made cross bolted w/427 caps. This is a 73 "C" heavy duty block.
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No shelf pistons in 4.200". There are a few choices in 4.190".
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Did you ever run that block with the 8 sleeves? Curious how it held up, most of the time when you sleeve all 8, after running for a while the block cracks between the sleeves up at the deck, causing head gasket issues. In fact I've never heard of one that survives for an extended period...
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No, I never ran it. The deck looks fine, the hairline crack is in the lower half. I would think it would be at the top where the pressure is. It's at the bottom of the cylinder and runs up about halfway. Maybe it had water and froze? Who knows. I guess the pistons would be 4.195 for a 4.200 bore? Who makes the 4.190's pistons? Thanks Brent. Also if this block was already sleeved, could it be sleeved again to bring it back to a standard bore 428? How many times could a block be sleeved?
If run at the 4.200 bore, I would probably put Medium Riser Heads on it.
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I’m using a 4.19 bore BBM block with CP pistons
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I think the general consensus is if it's had all eight cylinders sleeved it's not worth it trying to buy new pistons and time for a new block.
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i hate to brag on it but i had a 390 that was 30 over with 8 sleeves lasted 18 years before it cracked.
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Did you ever run that block with the 8 sleeves? Curious how it held up, most of the time when you sleeve all 8, after running for a while the block cracks between the sleeves up at the deck, causing head gasket issues. In fact I've never heard of one that survives for an extended period...
I've seen a few that lasted a long time. On a used up 427 block I would recommend a smaller OD sleeve and going to 428 based bore diameters - leaves more deck material.
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Let me add a little something here. First I don't like conventional sleeves and wouldn't buy a block with them but, one on each side might not be to bad for reliability. Still would buy one.
In my opinion, the worst thing, about multiple sleeves, is that they add radial stress to the block, because of their press fit (.002-.003 recommend by the mfg). So, multiple sleeves are trying to push the block a part, at each hole, along with the increased sleeve bore, weakening the block.
Now, since your block is already bored for sleeves, the holes will be 4.297. 4.3125, 4.360 or 4.375, with sleeves .003 larger. Those are std Melling sleeve sizes.
If your up for the extra work, you can relieve that press fit stress, by going to flanged sleeves, they come in the same diameters and you can install them with .000 - .0005 press fit. Lock tight them in.
The flange is 1/8" thick and can be cut so that they are up to .002 high, for better head gasket seal or, if the machinist has a problem holding depth, they could be left as much as ~.005 high and deck the block, after so, they are finished 0 to .002 high.
After installation, I would reduce the bore to 4.13 - 4.16.
Done like that, the block would have a much better chance of living, long term, I think.
Edit:
BTW, these flanged sleeves are stronger than regular sleeves.
Melling “HP” sleeves are made from centrifugally cast, high strength gray iron. It is a lower carbon iron
alloyed with chromium, copper and nickel to produce a harder (241-293 BHN) more wear resistant
surface. The average tensile strength (45,000 - 50,000 p.s.i) is 1/3 greater than “regular” iron sleeves
and nearly all OEM cylinder blocks.
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That is great info Frank. I heard about the step sleeves for an FE from Melling. Didn't know all available sources though.