Well what would be your preference and what are some pro's and con's?

either one would be great for me!

I assume your talking a 350 block with an overbore .030 versus .060 running a reground 3.75 stroke 400 crank

in havent kept up but in old days was always worried about core shift in the old sand castings & we would go .030 & have a future possibility of a .040 with next rebuild

also the old blocks sometimes would go out of round easier with a larger bore & seen cylinders crack because of thin spots

all my building experience comes from before 1990 when I used to build for people I knew & I used 1960s & 70s engines & I have built several hundred engines

there is good & bad with all engine choices even if you went with a 400 & destroke it alot of people do not like the steam holes & siamesed cylinders versus water circulating around the entire cylinder & the water passages. which is normal for all small blocks other than the 400. I personally didnt mind as I used to race Datsun L series engines & all their factory blocks were suitable for racing & had siamesed cylinders

the other draw back on the 400 is the larger bearing diameter as drag races feel it imparts a little more friction & some want to reduce friction & use cut down cranks with thicker bearings.

also with a stroker piston speed goes up & rpm will be less. I like big bores better with short strokes to rev faster but will produce less torque & use a little more fuel than engine built stroked to same cubic inches as more piston surface area If wanted a rev happy engine could use a 3.25 stroke late 327 crank in a .030 over 400 block & use a longer rod & have a lower piston speed & better rod angle

Randy