19's or 18's with taller sidewall tires would be the easiest and quite possibly the cheapest since you can always keep your stock wheels if you need to sell the 19's. I can't give you an exact relationship because there are too many variables and I don't know the figures exact enough off the top of my head. Going from 16's topping out at 160 is roughly 190 on 19's, same tire sidewall height. Why doesn't this happen often.. because the 19's almost always have extremely low profile tires compared to the 16's.

the PPG set is great for those who need it.

 

wow so expensive =\

 

yeah but its well worth it.

 

capt kirk

Im running a garrett 700 turbo with larger internals [approx 750hp rated]
The motor is a fully built toda 2.2 turbo setup with spec c cams , ported head and dry sump.It starts boosting at approx 5200rpm and my redline is 9100.
The easiest way to work out what u will need is to draw a gragh with speed and rpm represented on the x & y axis. Then draw in each gears [1-6] and see where they insect each other when u change gears. Work out what turbo and engine specs u are going to use and estimate where ur power in rpm will start and then make sure ur choosen gear ratios dont fall short in terms of boost.Remember my gear ratios would work nicely say with 2.0 and a hks gt3040 I spent time making show that the ratios worked for circuit, drag racing [hence 4th gear] and also for street cruising [6th ratio = 3000rpm at 100kph] goodluck