I have 205/40-17 on my S2

but Rick.. when you said S1 box, I just remenbered.. once I got my CTS box, I hit the limiter 6,25 mph earlier in every gear I think.. so I am possible running with a S2 box..

Rick: The standard 1.6 CVH geaqrbox has a 3.55 final drive, which gives 120kph at 3000rpm... anyone knowes what the S1 box have...

Im REALLY pleased with the box.. dont misunderstanmd me