fattest cam in a 340?

ive got 10 bucks sayen your ballencer has slipped man! my 72 cast crank 340 did the same thing. execpt i knew i set it @ 12 btdc & just checken stuff out after another intake swap & it said 3 btdc. lknew dam well that wasnt rite. sent it to damper dr. got er fixed & presto right where i left it @ 12 deg. also it should have a external ballance damper for 72-73 340 only man.