greybull

The guy at the machine shop is telling me that it needs at least the .030 bore... and after some reading Indiancreek's comments maybe the out-of-round hole is why he is figuring on the full .030 bore. I do not know if he is considering an offset bore.

I am doing the whole rebuild, was at first looking at a rebuild kit, silly simple me, but after all this discussion I am seeing that this is going to have to proceed in pieces due to the need to see where we are at each step. First the bore to get clean cylinders, then a piston choice, which has to be matched with a gasket thickness choice to get both proper quench and compression settings... at least as far as I understand these things. That research of course has taken me down quite a number of other rabbit holes here...

Indiancreek

Ask the shop if his boring bar will offset bore. Mine will so there may be one near you if his won't. Still requires sonic test to see where the hole is in relationship to the coolant area. Usually unless there has been excessive wear to one side of the hole, they will clean up at 0.030. How much lip do you feel at the top of the cylinders?
If you have a bunch of scoring in some of the walls, You must have gotten some debris or carbon running through your engine at some point.

greybull

I have not actually felt any of this, the engine is some 800 miles away from me. There is not any machine shop I trust close to me, that is why the engine went to a machine shop in Oregon to some folks I do trust there. So all of this is happening via phone and email conversations. Not exactly the way I wanted but just one of the joys of living where I do.

In his description of the cylinders, they were really pretty clean, but a couple of them had a couple deeper scratches. In his further engine teardown it appears that what has happened has to do with the 2 previous owners and their attempts at rebuilding this car. It basically has been sitting in storage since 1996, has had a couple folks that bought it, thinking restore, but then decided for one reason or another not to. What appears to have happened is that the car sat for quite some time, then one of the 2 previous owners decided to try and fire it up... as is. This appears to be when the damage was done due to having crude and crap in the engine from just sitting and not being properly mothballed, and then they spun it up. At least that is what the machine shop tells me they think happened here. The cam was somewhat flattened from use but no other signs of real wear or abuse. The lip at the top he said was minor, at first he thought a ridge ream and some honing and we'd be good. Once he looked deeper he found these other issues.

The sitting aspect is why I decided to do both the complete engine rebuild and the frame-off resto... I just don't trust anything that has been sitting for this long.

Indiancreek

My opinion, and just that. If the engine had a fair amount of miles on it and he once thought it could be ridge reamed and honed then I'd go someplace else.
If he uses a rigid hone and sprays a guide coat of paint on the cylinders take a quick pass with the hone and see how egg shaped the holes are. It's difficult to hone a block round again once it's worn. Especially a small block chev. having to deal with the main saddles on 6 of the cylinders.
Get'em round with a bore and a good hone and your new rings will love you. You can have the deck checked for flatness and may not need them decked. Just have to look. Anyone with a good bore gauge can tell you how far out they are.
Get the rods reconditioned as they will be out a little too. Turn the crank and balanced and you'll be on your way to another 100,000 or more.
While it's apart recon the heads too.

63mako

Going from a ridge ream and hone might do it to I need a .030 overbore at least is a BIG difference. Many shops just go .030 over as a standard practice on any overbore. On a small block numbers matching that takes you to no later possibility of a future rebuild as very few sonic check well @ .040 or .060. A scratch in the cylinder would have to be really major to not come out @ .020 over. Get some good measurements and do a minimum bore on the worst cylinder and see where your at.

greybull

Indiancreek, 63mako, I cannot thank you enough for the advice here. I was severely under-understanding this. I've a feeling that you're opinion that "just go to a +.030 overbore" as a matter of practice may be the case here. As I said, where I live there is no one I trust here as the locals will go at it with a flat file here, so I went to this shop as they were recommended by other folks I know that have had work done there, but in pushing this further I realize they asked none of these questions.

I'm backing up on the whole thing here until I can verify what these folks know for sure, or can find someone that knows these things and does them as part of their regular block checking procedures.

Which brings me to the obvious... I am in SW Montana, basically on the moon as far as folks that know how to work on 42 year old engines or Corvettes period. So, any advice on shops this part of the country? I already sent it to Oregon, so moving it somewhere else I am willing to do, would just rather do it only once more from here.

Thx again.

Indiancreek

Every block doesn't necessarily need align honed or decked so let your shop that you pick inform you of their opinion. The unfortunate issue is the shop makes more money the more operations they perform on your engine.
However any money you put into torque plate honing and balancing will be money well spent.
As you get information regarding the rebuild from your shop, post it on this thread and I'm sure you'll get opinions about the results. Feel free to send me any questions you may have as this unfolds. I'm sure others will tell you the same thing.