.004" per inch of bore on the top ring & .003 on the 2nd ring per inch of bore(for non KB hyper pistons), for you it'd be 15 tho & 11 thou. 30 is too much but it would work but it would work much better with a tighter set of moly rings or may even require the extra $$ for a file fit set. The amt of wear plus the honing opened it up a bit & since circumference = Pi X diameter, a .001" increase in dia(from the honing/wear) will increase the ring gap 3.14"