Opinions on sleeving for a 470

[7t500]

400-470, built in 2019. Less than 1000 miles on it. Sonic check results in attached picture. Only a mild ~500ish hp build with ~10:1 compression.

I found water in my oil and after taking the heads off I found a cracked cylinder wall on cylinder 1. I took the engine out and found another crack on cylinder 4.

Now it needs at least 2 sleeves and after looking at the sonic check results closer a few other cylinders have me nervous... what would you do? Spend the time and money finding a new block or spend the money on sleeves and run it?

 

[R413]

How much will sleeves and machine work cost you to have it ready to assemble? Some say sleeves make a better block for higher power.

How do you know a replacement block will be any better than what you have?

Sad to have happen on a new engine.

 

[33 IMP]

Balance the purchase and machining costs of another block (which,as pointed out may not be any better than what you have), against several sleeves in your block. Agree with the fact that a sleeve, properly installed, can be much better than the original hole.
I would lean toward the sleeves. Kinda depends on having a good machine shop that you trust.....

 

[steve340]

I would go for another block. The cylinder block is the foundation of the engine.
Build a house on sand no matter how strong you build the house it is still sitting on sand.

 

[33 IMP]

May we ask, what year and casting # is your block?

 

[69Bee]

Was the sonic test before or after it was bored? If before, how much came out? Not all sonic testers can show interior pits on the inside. That said, just putting 2 (or more) sleeves in might solve the problem for those two, but sleeves are an interference fit, and WILL impinge on any adjacent cylinder requiring honing of those cylinders also. In my shop, sleeving will run about $110-$120 depending on the cost of the sleeve, then boring & honing to size as I am sure it is not currently std. Getting another block will require sourcing block, cleaning, sonic check, align hone, squaring, boring, and honing all over again. Sleeving the current block might cost less, but how might the other cylinders be; just like the two that already cracked?

 

[Gunner1]

For a mild build it might not matter. But for a race motor a sleeve reduces the material connecting the crankcase section of the block to the deck. I have seen a loss of deck integrity on small block ford and chevys when multiple sleeves were installed on the same side. Leaky head gaskets were the first clue, Then warped decks. Just a thought. I dont know the deck thickness on a B block.

 

[4speed68rt]

It looks like its cut too thin!! The other 6 cylinders cant be much different. Just a matter of time before they all crack. Weakest link will break. Something's not right. I would re-evaluate the whole engine and probably build something a little less volatile with whatever I could salvage from that.

 

[IQ52]

You are missing about 2/3 of your sonic test measurements but the ones you do have, if correct, are very good. Something else is wrong. The block shouldn't split with those thicknesses.

 

[66Satellite47]

Gee, 1000 miles is not much. In the '80's I built 2 400/451 motors. They were 7000+ RPM drag motors. Each over 350 runs, one may have cracked one cylinder, not sure. They did use up the stock 440 cranks at 7000+ RPM. May all depend on what the 470 combination is. I'd get another block and sonic check it before spending a lot on it. I'm not a builder, just a user of what I get built. My 400 blocks were not the "230" block.

 

[dvw]

Looking at the sheet, the thin areas are not on the thrust surface. Where were the cylinders measured? Top, middle, bottom? Or are these numbers the thinnest areas? #1 in the sheet shows that area to be between .183"-.312". If the measurements given were the thinnest spots I'm surprised it's cracked.
Doug

 

[66Satellite47]

My 400 blocks compared really close to most of the 440 blocks we tested. The numbers on the chart look pretty good. The crack shown is not like anything I would expect.

 

[7t500]

How much will sleeves and machine work cost you to have it ready to assemble? Some say sleeves make a better block for higher power.

How do you know a replacement block will be any better than what you have?

Sad to have happen on a new engine.

Sleeves are going to be ~$200 per hole plus decking per the machine shops I've contacted. So far I'm in the $500-1k range with 2 cylinders, assuming no other issues are discovered.

There is no guarantee that another block is better and that's part of the gamble.

 

[7t500]

Balance the purchase and machining costs of another block (which,as pointed out may not be any better than what you have), against several sleeves in your block. Agree with the fact that a sleeve, properly installed, can be much better than the original hole.
I would lean toward the sleeves. Kinda depends on having a good machine shop that you trust.....

I would go for another block. The cylinder block is the foundation of the engine.
Build a house on sand no matter how strong you build the house it is still sitting on sand.

These are the two thoughts I keep going back and forth on...

 

[7t500]

May we ask, what year and casting # is your block?

4006530 cast 7 14 75

 

[7t500]

Was the sonic test before or after it was bored? If before, how much came out? Not all sonic testers can show interior pits on the inside. That said, just putting 2 (or more) sleeves in might solve the problem for those two, but sleeves are an interference fit, and WILL impinge on any adjacent cylinder requiring honing of those cylinders also. In my shop, sleeving will run about $110-$120 depending on the cost of the sleeve, then boring & honing to size as I am sure it is not currently std. Getting another block will require sourcing block, cleaning, sonic check, align hone, squaring, boring, and honing all over again. Sleeving the current block might cost less, but how might the other cylinders be; just like the two that already cracked?

Checked before boring and was bored to .035 over. Soundsike we have very similar concerns about the other cylinders.

 

[7t500]

You are missing about 2/3 of your sonic test measurements but the ones you do have, if correct, are very good. Something else is wrong. The block shouldn't split with those thicknesses.

I'm very curious as to what "something else" may be as it barely got used and wasn't really beat on at all... I'm frustrated and confused as to what caused this.

 

[7t500]

Looking at the sheet, the thin areas are not on the thrust surface. Where were the cylinders measured? Top, middle, bottom? Or are these numbers the thinnest areas? #1 in the sheet shows that area to be between .183"-.312". If the measurements given were the thinnest spots I'm surprised it's cracked.
Doug

Great question and I should have asked the machinist more about it when I had it done. He was confident that it was solid and there would be no issues since he could offset bore it to compensate for a couple of the cylinders.

 

[7t500]

My 400 blocks compared really close to most of the 440 blocks we tested. The numbers on the chart look pretty good. The crack shown is not like anything I would expect.

Have you seen anything similar? Short of a thin cylinder wall, I'm not sure what causes this. The car is stored indoors with thermostat at 55-60 year round. Car is barely driven lately due to a 2 year old and life...

 

[Gunner1]

I would love to see a sonic test done all around your crack. That would tell you a lot more info about a possible why.