cesar, i'm not mr. theveed pero i want to share my idea.
i think hindi nila kailangan i top overhaul yan. kailangan lang i-replace yung valve seals. and tama si mr. theveed. if ever due na rin for replacement yung timing belt mo, pwede mo na ring isabay yan.
ang magiging effect nyan if ever is insufficient burning the fuel dahil basa nga yung plugs mo ng langis, which will also result in higher oil consumption and higher smoke emission.