Heads gasket
#2
i don't think it should matter? what size shot are you planning on using? if its nothing more than 150, then it shouldn't matter.. Your concerns should be on you pistons, rings, rod/main bolts instead.
#3
Actually the motor is built for nitrous, this is the problem the first time I use nitrous I when't with 150, I did like 4 runs.... Afther I change my jets to 100shot I did 2 runs and that was the end of my head gasket. My concern is if I was running too rich? Or what cause this? I agree with u 150 is not a lot for a lt1!..