318 to a 390 or 392 stroker?

.030 or .040 is there really any difference here? If you "feel" safe at 30, 40 should be good too. We are talking about .005" a side, or the thickness of a sheet of printer paper. Not going to make a hill-o beans at this point. Now if you were talking about going .030 OR .130", then you really need to have it looked at by a sonic tester. But to say you will be safe at 30 and iffy at 40, thats BS. If its not safe at 40 it aint going to be safe at 30 or even std for that matter.

But Im all for the LEAST amount of over bore, if it cleans up at .010 and we have a piston/ring combo that fits that bore, then thats what it gets.