Stroker or Not

AutoX

X heads. 2.02 1.60 Rebuilder is tops on porting. So for a few hundred more why not? That is provided the heads are OK. Are the exhaust valve seats hardened? If not we may have problems since I am fairly sure a lot of my leakdown is from valves. One cylinder likely has a broken ring cuz it dumps a bunch of air to crankcase.