no lah.. i think every piston got that.. even motorcycle piston got.. usually that's the size to determine how many time your block rebore already (normal condition, not saja2 rebore like me ahahahah)
let say ur blocks it's virgin.. so the marking on piston the will be 0.00, then by time the cylinder wall makan, need to rebore.. then machine shop will rebore 0.25 mm, u need to change piston 0.25, next will be 0.50 then 0.75 final 1.00, that's the allowable rebore size by manufacturer 1mm only. So the engine lifetime is only 4 times rebore, else need to changed the sleeve.
Normally mechanic will call that number twentyfive, fifty, seventifive and hundred.
So mine it is equivalent to 92 piston 2 times rebore.. got it? :D
