Fast is a relative term. Maybe you should consider selling the 50 and getting a 150.
I would argue that the 150 is not "Fast" either. Scooters can be "Quick", maybe "Agile", but not "Fast.
All this de-restricting and modification sounds like a pain in the ass to me for something that is inherently slow.
In any case, it is hard finding proper performance parts for the Super 8, 50cc or 150cc models.
I do like my 150 around town and it is quick enough to be safe and fun.
Good luck.