Verified answer

For the cost of doing it correctly, you'd probably be better off just selling your car and buying a 135i.

Bmw 128i Turbo

You can not modify it as a single turbo since it has twin-turbo 3.0-liter I6 good for 300 hp, and designed to deliver high performance by the twin turbo. You can know about turbochargers, refer this link: http://www.turbochargerpros.com/

Yes it is avery possible, if you have $7000.