speedometer recalibration

[gonzomania]

I'm trying to decide what size tires & wheels to buy. I have stock 15" wheels now. Went to do it yourself link and search only yielded two recalibrations, not sure if this has changed for newer models.
Mine is a 2003. If you go larger does anyone know how much this effects the calibration? Also does width effect calibration?

[IRPT]

gonzomania, check out these two links. This should give you the information you need. Keep the difference between old tires and new tires to plus or minus 3%

Width does not affect calibration.

http://www.dakota-truck.net/TIRECALC/tirecalc.html

http://www.miata.net/garage/tirecalc.html

[bobs turbo pt]

i put gt rims on my wifes 02 base model pt everything works great

[Jimbo]

IRPT thanks for the link.