good that ur enjoying it... doesn't the fact that the sidewall is 30 as opposed to 35 make the speedo reading slightly wrong? and how would it be if they were 275/35/19? did you change your front tires?
once again, i say. isnt the speed picked up via wheel speed sensor. aka not in the driveline. so tire size should not matter.My 2 cents if I may:
overall diameter of these various tire sizes.
OE: 255/35/19 overall diameter = 26.00 inches
275/30/19 overall diameter = 25.50 inches
275/35/19 overall diameter = 26.50 inches
About a 1/2 inch difference in O.D. either size from factory. Divide that 1/2 by 2 since it's a round tire and you end up with about a 1/4" difference top and bottom from factory spec. Not really enough to make significant difference in the speedo IMO. Probably would be off be 2-4 mph.
search the forums for a thread where they put a 4.08 rear differential in the IS F. factory is a 2.93 rear gear. it was a dealership that did it, im not sure who, i cant remember. they said they drove 2 IS F's side by side, one with the new diff, one without, and the speedo's were exactly the same. so if the diff gear change doesnt make a difference, why would tire size.I wish someone could verify what Doublexl is saying. I will check with mile markers as soon as possible.
If you change the rolling diameter of the tire, that will affect the speedometer. A wheel speed sensor is reading rotation of the wheel. If you change the height of the tire that will change the rotating speed of the wheel. The size chart I presented was to show that we are splittin' hairs with sizes discussed vs. OE.once again, i say. isnt the speed picked up via wheel speed sensor. aka not in the driveline. so tire size should not matter.