got car back after changing all gaskets including heads. Drove ok, than the temp starting fluctuating......hot cold cold cold hot..... than the car makes a weird sound and white smoke starts POURING out of the dumps. The car starting driving...well felt sorta like the feeling you get when your spark plugs arent hooked up right. Didnt even give the car much gas. Did i fry a piston, blow a head gasket, or could it be the lower manifold leaking where the crossovers are.....coolant/oil passage? I dont know what to do... 

