KC10Chief

I was planning rebuilding my engine this spring. Should I know before hand if my block will need to be bored? How can I tell by looking if it needs to be bored over? About how much would I expect to pay at a good machine shop to have my block bored over? Would it be the same to have it bored .030 over, as it would be to have it bored out to a 383? Also, if I DID have it bored out to a 383, would I have to change a bunch of stuff like the cam or the computer stuff? Sorry if I am beating this to death. These are probably common questions but I haven't been able to do searches for the past couple days for some reason! Thanks for any info! Matt

demonchild

1) you can tvore an engine to a 383, you stroke a 350 bored 30 over to a 383 by using a 400 crank.

2) if you have the stock engine from 88, i would say you need to bore it, no matter the circumstances.

3) if you are going to be rebuilding an engine, it looks like you have a lot of reading to do.

ede

you can't tell if a block need bored by looking any more than you can tell if a crank needs ground by looking. measure the crank with a mic and measure the bore for out of round and taper with a bore gage.

AJ_92RS

Or you can do what I do and take it to the machine shop and ask them.

That's really the best way. They can also tell you what else it needs while it's there.

Like resurface the deck, align hone the mains, throw it in the trash because it's starting to crack, etc.

They're profressionals (or at least I hope the ones near you are) and they know what they're doing.

jpk91rs

If you see scratches in the bore, it needs to be bored.
If you see scratches on you crank journals, you crank needs to be turned.

AJ_92RS

How much?

And how do you know a hone wouldn't be enough, unless you measure?

Quote:

If you see scratches on you crank journals, you crank needs to be turned.

How much?

And how do you know a little sanding and polishing won't be enough?

jpk91rs

Bear in mind I am speaking of scratches or gashes in the cylinder wall, but the general rule of thumb is, if you can hang a finger nail in the scratch it need to be bored to the next oversize. Same with the crank, except it will need to be turned to the next available undersize.

ede

that's a pretty foolish way to determin the need for or amount of machine work required on an engine. i'll stick with mics, indicators, and bore gages. i wouldn't trust a shop to tell me what i need either since the more you need the more they stand to make.

AJ_92RS

Then you need to find another machine shop.

ede

there isn't any i'd trust. i'll stick with doing my own measuring.

ploegi

Yes, I agree, the only way to tell for sure what kind of work you need is to measure the block/crank. If you dont have the equipment to do so, then you will have to pay someone to do it, or, rent the equipment to do so. If you have no experience using the measuring equipment, you would be MUCH better off taking it to the machine shop, and having it checked.

Finding a trustworthy machine shop can sometimes be a problem. Ask folks around that have been to some of them who they think is best. Also, check with the local car dealerships, and see where they have thier machine work done........