i'd either look for a new set of heads or what about thicker head gaskets? i don't know a whole lot about the 302's, but it might be a thought.
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91 ranger, 88 tc 2.3 turbo, stroked, bored, 5.5" crower connecting rods, wiseco 8.0:1 dished pistons, total seal .030 rings, fully ported iron big valve head, racer walsh turbo roller cam, bobs log, holset wh1c, fmic, full 3" exhaust. not really a whole lot left to do.
93 explorer 4x4