Aftermarket question?

[RyanosAlien]

Hey,

This question for you aftermarket gurus and I'm sure this has been covered a million times so I'm blaming this on being a newbi but are those cdi and coil kits on eBay actually improve performance or do I need to get like a intake and jet kit to get any decent gains and if you all have any suggestions on brands or makes please let me know, I'm a bigger dude and the gy6 150cc I'm afraid is not going to cut itlol