What would you do,???.

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barracudadave67

barracudadave67

FABO Gold Member
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Working on my stock bore 1975 360, and this is what I found on cyl #3 high on the side. Bad pitting. Don't know what course to follow. I had not planned on a rebore, just clean the block up good, and a real good hone, with new Keith Black pistons, Scat Rods, new rings, bearings etc. All other cyls are fine, just #3.
The pitting is pretty deep, probably .050inch at deepest spot.. I'm stressed out on this, had this block a long time never knew it. Was going to install it in my 66 B-Cuda. Don't have big bucks to play with.

Dave

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You can handle it one of two ways, IMO. First, if it doesn't have much of a ridge, "I" would dingleberry hone it, rering it and let er rip. Those pits are barely if at all inside the ring travel. It wouldn't bother me one single bit as long as the ridge is not too bad. If it has a pretty bad ridge, bore it.
 
I agree with Rusty. I have a 318 in my truck just as bad.Not in the ring area,but close to the top ring.Just honed to clean up as best as I could and that was 6 years ago.Been driving it everyday.Us low buck guys gotta do with what we got.
 
Rusty
No ridge. Thats how I found it. I was removing what little ridge it had. All cyls hardly had a ridge. You can still see the cross hatch in cyls.
I was thinking the same just hone it good, and install new pistons.
The stock pistons come right up to the bevel ring which is visible in the pics. I don't know where the rings are on the KB pistons yet as I don't have them yet.
I really appreciate your knowledge, on these matters.
Dave
 
I'd run it. Re-ring, that's it. Don't waste money on better parts. One hole will be lower output, and it might push oil if you hammer on it due to blowby. It also might not...
 
In the first pix, is that deep pitting down as much as half an inch from the top of the bore? It looks like it, but the pix is out of focus, so I am not 100% sure.

BTW, I would expect KB pistons top ring to come somewhere around .080-100" up higher in the bore than the stockers. The rings are higher on the piston, and the compression height is taller too; both push the rings up higher in the bore. So any ridge is gonna have to come out IMHO, but a beveled ridge reamer is gonna take the cut down below where the top rings travel, so that is not good.

If you are going with new pistons, and the cost of some new SCAT rods, and the re-balance work that is going to be needed, I can't see shortcutting on the block. IMHO, another block if the pitting is down as far as it looks in the 1st pix.
 
barracudadave67 said:
Rusty
No ridge. Thats how I found it. I was removing what little ridge it had. All cyls hardly had a ridge. You can still see the cross hatch in cyls.
I was thinking the same just hone it good, and install new pistons.
The stock pistons come right up to the bevel ring which is visible in the pics. I don't know where the rings are on the KB pistons yet as I don't have them yet.
I really appreciate your knowledge, on these matters.
Dave
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If it was mine and I didn't plan on tearing it down, I'd run that beeotch. If you're going to tear it down, rering it and run that beeotch. I think it'll be fine.
 
Could you post more pictures? That looks deep, If it is, then this is not a candidate (as is) for KB pistons and Scat rods!
 
Heres a couple better pics. The pitting is just 1/16-1/8th shy of half an inch down from the deck of block. It has one deep hole their. The ring just below the deck is where the stock piston is at TDC, it is a bevel.
I'm boarder line on the use of the block myself.
Dave

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I doubt they are as deep as you think, I have had 2 blocks that looked like that. I took a 70 grit dry sunnen hone and and opened them up till they were gone and the worst was .020 and they looked worse than yours.
 
I'd run hell outta it. I think you're over thinking it. It's yours though so do what makes you comfortable. Keep us posted.
 
I'd sleeve that beeeeeotch in a New York second. I keep the press fit at .0005-.0008 max. That way you don't distort the adjacent bores. Hone the mother and go. A sleeve is cheap money.

BTW, if you brought a block to me that you ridge reamed it would either be bored or I'd hand you my list of other machine shops in the area. I don't put my name on stuff like that. If it had a ridge that needed to be removed, it needs to be bored.
 
brian6pac said:
I doubt they are as deep as you think, I have had 2 blocks that looked like that. I took a 70 grit dry sunnen hone and and opened them up till they were gone and the worst was .020 and they looked worse than yours.
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.020 might as well be a mile. That's a bunch. Of I'm reading this correctly, you took .020 out to remove the pits. At that, I'd have left them in there.
 
yellow rose said:
.020 might as well be a mile. That's a bunch. Of I'm reading this correctly, you took .020 out to remove the pits. At that, I'd have left them in there.
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There was a lot and it was std bore 340 the machine shop said it was junk, too rust pitted. When I said .020 I meant total so .010 deep, the block cleaned up at .030 and made a nice engine. You wont know till you open it up and see what it takes to get rid of them.
 
No.... I did not take anything off/out of it. Their was hardly any ridge, it was mostly carbon build up. This engine is stock bore. It sat for a long time before I bought the short block a year ago. The corrosion is on the rear side of the cylinder wall, which I don't understand, and not the bottom. All other cyls are really clean. I'm not much of an engine guy. I'm using my book "how to rebuild small block mopar engines".
Dave
 
brian6pac said:
There was a lot and it was std bore 340 the machine shop said it was junk, too rust pitted. When I said .020 I meant total so .010 deep, the block cleaned up at .030 and made a nice engine. You wont know till you open it up and see what it takes to get rid of them.
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That makes sense then.
 
barracudadave67 said:
No.... I did not take anything off/out of it. Their was hardly any ridge, it was mostly carbon build up. This engine is stock bore. It sat for a long time before I bought the short block a year ago. The corrosion is on the rear side of the cylinder wall, which I don't understand, and not the bottom. All other cyls are really clean. I'm not much of an engine guy. I'm using my book "how to rebuild small block mopar engines".
Dave
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I won't lie to you. The guys telling you to dingleberry it and let it eat are correct. It will most likely never know it. It's different when you do it for a living and your name is on it. Look what happens on these forums when everyone with a keyboard has done it all.

Since I can do the work, id sleeve it. Best fix and you only need to fix one hole if you do it correctly. If you don't have the mnmal money, or the time or just don't want to screw with it, hit that beeeeeotch with the berry hone and don't look back.
 
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Tnx for the new pix. IMHO, there is the discussion of stock pistons and rings, vs KB's. If you use the KB pistons, the top of the top ring will be right about .285-290", or a bit more than 9/32", below the deck, and will hit any ridge in the bores. So let that be your guide if you continue with the KB plans. It looks like the ring will travel over that one pit down near the existing ridge. Whether or not the KB rings will reach that large group of deep pits further up, you'd want to measure for .285" or about 9/32".
 
This is just for fun,,, back in the 60's the car guys I hung out with had a saying,
"Build them loose,they'll take the revs" Some things you never forget .
 
If your not going to clean it up and put in oversized pistons, then why not re-ring the pistons in it - no sense risking new parts on a half a$$ed build.
 
I totally agree with running it. Hone it and throw whatever parts you want at it. If you did wind up with a problem (which I seriously doubt), what will you be out? A gasket set and the cost of a 360 block? You would only have to find another 360 block and have the cylinders matched to the pistons and rings you have. On the other hand, gregpurcell is correct when he says that 360 blocks are not terribly expensive. the choice is yours, but I would hone it and press forward.
 
Dingle ball hone it, and put one of the stock rings back in it, with no piston.
Use a bright light and shine upwards to the ring, when you see no daylight showing thru, the ring will seal.
This will cost you nothing more than time.
 
I was looking up your inquire and in the heavy machinery/farm tractor forums, their recommendation is to hone and run. I 'think" they say to use cast iron rings, not chrome rings. Maybe a moly coated ring would fill in some imperfections? Had a 340 that one cylinder had .008" piston to wall clearance and ran fine. Guess you could hone it a bunch to try and remove the pits. Good luck!
 
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