There won't be any disadvantage when converted to 1.6 clutch kit as long as the measurement of weight, length of fltywheel, pressure plate and clutch plate are right...
Me myself already using it... well, burned a 1.5 4G15P Wira, 0-100km/h in 11sec. using 15" JRD rim... ok or not, you decide...
Anyway, when people tell you clutch kit convertion can be done in RM400-RM500 with all the skimming and modification, let me know, i would be interested to talk to him...
Top Speed of 190-200km/h, yes it can be done but for MMC engine, not VDO engine...
Anyone who wants to know more send me private message for any question, i'll answer it all with details...