Changing tire/rim size Probs with speedo misreading?

I am going from stock 16's and 245's to 275/17x9.5, will I need to recalibrate the speedometer?

No. The stock 245/50-16 and the 275/40-17 are both approx. the same outside diameter - 25.65". You can even go to a 315/35-17, which is approx the same diameter. No speedo corrections required.

thanks