Typo on my part. They’re actually 45 series tires. They’re exactly what Tire Rack.com says to put, so I did. I don’t think my speedo’s off.(haven’t been pulled over for speeding yet…)
ideal rim sizes for 215 width tires:
16x7", 16x7.5", 42-43mm offset
17x7", 17x7.5", 42-43mm offset
18x7.5", 42-43mm offset
important points:
not all tires of identical size are made to the same width - there can be variances as much as 1/2" between manufacturers of the exact same number size tire.
wheel offsets have to do with how close or far the tire will be to the strut or wheel well - a lower number offset means the tires are closer to the fender, a higher number offset means the tire is closer to the strut.
as for tires and speedo calibration, approx 23.5" OD is what the 120mph speedo and pcm are calibrated for, so here’s a list of tires that will make a negligible difference to the speedo:
205/55/16 rubbed on mine. Granted mines also the S/R so its got the lowering springs on it. But did find a set of 15s I like but want to a little bigger then that
Any 205 will fit provided you pay attention to the wheel offset. 40-43mm offset would not cause rubbing even with lowering springs.
but 205/55-16? thats 1" taller than stock, so although it may be good for mpg, it’s going to hinder performance and throw off the speedo 5% (70mph indicated is 73.5mph actual). Its like changing the zx2’s manual trans differential final drive from 4.10:1 to 3.89:1