imo any coolant loss is way bad news
id say the block not flat of theres a crack some place
do you get bubles in the rad when the caps off? when ive seel cooland compsion ive seen bubles in the coolan with the cap off as the combustion pressure makes its way into the water jacket and then when the engines in the intake stroke it pulls coolant in and burns/pushes it out the exhaust in a big white cloud of smoke usaly
are the 22rs bad on head gaskets?