well apparently when my dad had the motor rebuilt last time <5 years ago> the heads were suppose to be alls tainless valves and 1.94 1.6 they guy tore em down and they were el cheapo stainless intake 1 piece with 2 piece OEM 1.5 exhaust valves and a shitty port job <i could tell that much. now they are 2.02 1.6 hes blending the bowls port matching the intake. and milling the heads a little. so it should be a very noticable differnence also going with 10*degee locks n retainers and most likely K-motion springs those springs were pretty wore out at 1.8 something installed height they had like 100 closed and 200 open whoa those were wasted!