My first post so go easy on me. I got a 331 sbf nice motor I freshened the short block long story short get the heads clean and find two hair line cracks under neath the valve seat Has any one ran across this ? Will it hold up if I repair it? Will have about a 40 jet on one kit It's a nice motor Very good shape I hate to just write these heads off. It takes 5 weeks to get a new set. Bes built the motor. Any info is appreciated.