I've been doing some measuring & came up with some numbers that aren't good, but aren't all bad either.
The limitation on the 270 with a .040 overbore is 3.820-3.822. My fattest cyclenders are 3.181, but I do think some of the scoring in the rusted ones is still too deep for that.
Maybe there is hope if the 302 pistons have the same pin height, since the standard bore is 3.999-4.001, it's not much of a stretch from the 270 bore. even if the pins heights are different, there's enough 4" pistons out there, I should be able to match something up from the vast array of V-8 parts out there. I hope.
Time to blueprint one of the pistons & start digging.
1956 GMC 370 dump " 'Tater "1970 VW Volksrod "the Black Bomber"
2007 Chevy Avalanche
2020 Jeep Cherokee Trailhawk,
2005 Harley Davidson FLHTCUI
I dig all cars, old and new, whether they were hammered out of American iron, German steel, or Japanese tin cans. Being unable to appreciate them all is missing out on a world of great things.
But thats just MY opinion! :P