I got a 71 340 block that's bored .040 over, the machine shop did a sonic test and said it has .275 in the thrust and that was good. I can't afford an R3 block yet, but I want to build a stroker using a 4.250 crank. So, my question is Can a factory 340 handle a big stroke using 2 bolt mains? Engine will see 6k rpm max.