I recently put on some 225/55/16 blizzaks on my car and noticed that it accelerates a tad slower. Which got me thinking that my speedo might be off as well. Check with a GPS and it is about 3mph slow. Makes sense as the tires are almost an inch bigger in diameter. I thinks a bit more (brain starting to hurt wiht all this thinking) that my speedo is off when I run TT wheels/tires out back, and wonder if nissan corrected this. Sure enough looks like there is a blue and a green gear. Calculated overall diameter of a stock TT tire is less than a quater inch smaller than the NA. Those nissan engineers really did think of everything. 225/50/16=24.86" diameter 225/55/16=25.74" 245/45/16=24.68" I am sure this is nothing new, Carry on
