big block 302cid V6!
Buddy in HS had a 305 V6 in his GMC pickup.
chvlfrk said:283 crank ain't goin in a 350 block without bearing sleeves.
There were special bearing shells specifically for this purpose: TRW MS3110P, but it was 35 years ago that I was doing this kind of thing; 283s were more common then.