Correct wheels for improving 0-100 time?

[kurwa311]

Correct wheels for improving 0-100 time?
My 9-5 got around 340HP 420Nm, AT gearbox and 18x8 rims with 235 40 R18 Michelin PS3. Best 0-100km/h time archived is 6.6s while starting in auto mode (S) without stall start. I do not have enough grip until 80km/h. I know that is bad for AT but I want to change wheels.
Rims: I would like to use 16 inch, since it is lowest possible with aero brakes. Smaller rim should improve my start since it will be easier for car to move centered weight, so my 0-20 time should be better. Also as I know higher profile tires is better for grip on straight line.
Tires: Half slick. Not sure which one. As I heard Toyo 888 will do it well and will ok while raining.
Tire size: 225/50R16. I wanted to use 235 but they simply not available. Other tires will be too big.
Rim width size: 225 50 is designed for min 6 inch, rec 7, and 8 max. Which one shall I use? Just smallest 6 inch for lower weight? Or 7 just because it is recommended? Or maybe 8 and hope for better grip?
Any recommendations?
If someone experienced with drag racing, how much time can a save with new setup?