I have a 350 that has had block work done to it. It has been bored and the block cleaned and new freeze plugs. The block is painted orange. BUT!! I bought this 350 block from a guy and he said when I bought it that it was bored .020 over. Now i know not to just take his word for it but the only thing i have to measure the bore is a digital caliper. It measures 4.02
Is that a good enough measurement to say it is 0.020 over, or should i spend the money for a bore gauge thats 100 dollars and i'll only use it once?
I need to know so I can rebuild the engine and i need the measurements before i can order parts.

 

Odds are it probably is .020 but its really hard to say. I really wouldnt trust it based off that measurement though. I mean what is the tolerance on that caliper? I mean if it was accurate to the +- .01 in that would make a big difference in this case. Not to mention human error. Also is this a freshly bored out motor or a used one? If its fresh im not really worried but if its used you'd want to give it a through checking over anyways. Im sure there is a way around this to really figure out for sure what the block is bored out to but at the moment im at a loss for a clever solution. Anyways even if it came down to buying a bore gauge I think it would be better to just take it to a machien shop to have them measure it for you. Shouldn't take long just toss a few bucks there way to say thanks.

 

according to my caliper specs. it is supposed to be accurate to .0005 in. And the engine has never been put back togeather after the machine work was done. its still a bare block and its wraped in plastic setting in my house.

 

I feel safe in believing it.