Just need some free advice if I can get it. I posted a while back that I windowed my aluminum world products RB mopar block. I borrowed a mill and cut out the broken sections, made some repair pieces, and had it welded back together, turned out really well, hard to see where it was broken. Took it to my regular engine machinist to get it bored for the damaged hole, and it needed a .010 bigger outside diameter sleeve, on the welded hole to make it straight, which took a month to get. The other bores had many runs on them and a few scratches, and as it turned out a little distortion from the damage and repairs. Anyway 4.50 bore is the next practical size to take it. The stock sleeves are 4.685 outside diameter, and with the 4.5 bore that leaves .185 and divided 1/2 that should leave .0925 wall thickness, dry liner pressed into aluminum about 1/2 inch thick, from what I saw on the damaged hole. My machinist thinks it will fly, what do you guys think? Camshaft fits in and spins free after the welding, so I think it might just be on the road to getting fixed. Mains look good with a straight edge as well, will see more when he align hones it. I have never tried to fix a block damaged this bad, just nervous I guess.

I can't believe using a sleeve with a .010" larger OD is going to hurt anything.

I've been as thin as .065 before. Would depend on what you're doing with it for me. NA I wouldn't think twice about it. Nitrous, or forced, I'd be really careful with the tune. Wouldn't take much detonation to hurt it.

Given that you have 1/2” of aluminum surrounding the sleeve, that’s where your strength is coming from. I’d say you’ll be more than fine

Where is the aluminum 1/2" thick ? Not between the bores.

How do you get one with nice thick sleeves......

Been wanting to go back to aluminum, and it seems the Indy is the only game in town......This was our complaint. Our block, as received at 4.490 bore had .011 taper and .008 out of round.

That block was the worst machining.....Some of us are not made of money, nor do we like to sit out season after season.

I have called to get a KB time and time again.....They have nothing....nothing in stock, no timing, no status.....nothing.

I would never go that thin with a big arm in it. Ours scuffed out the thrust side of the cylinder wall cross hatch with a 4.75 arm in it...The pistons are so short they shingle in the bore and rub out the cross hatch. If you go thin, keep a shorter arm in it so the piston skirts are longer.

Machining has to be dead nuts with .002 clearance in an aluminum motor......Our CI block, no issues, had it apart a couple times now for other reasons. Bores are gorgeous. But you can't get a CI block.....

No the .010 over sleeve was not an issue, the issue was stress from the rod breaking, pressing in the sleeve in the welded hole, and warpage from the welding distorted a couple of the cylinders, block was a 4.440 so 4.150 was the next size everything would clean up at.

Nostalgia super stock, so yes its NA, Thanks I was just wondering how thin you could go.

Yes I know, I bought this world products block 10 years ago and its been a good one. So I had to fix it, as you say nothing to replace it with. I called world products and they said sometime this summer they were planning to start making blocks again, and wanted $500.00 to reserve your spot when they start making them again, and at over $6,000.00 I just decided to spend a couple grand fixing mine.

We have had a couple World blocks. As long as they don't drill the head deck holes into the water jacket, I would buy another in a heartbeat. We have a CI one in the car now, and it's been a great block.