Originally Posted by VS_Rody

Hi flex82,

You can take the rebuild kit of the VSR01(same as VSR02), VSR03 or VSR04.
They are all compatible and have the same timings.
The main difference between the VSR01 and VSR03 is a small change in the shape of the exhaust port and boosters, while the VSR04 has some additional machining on the intake ports and also a lighter piston.
The lighter piston will allow you a better top-speed.

Hope this has helped you further.