With my calculations this is only going to be 6/10ths of an inch taller sidewall. Is there going to be any ill effects of this other than my speedo being off by a few mph?

These are the tires I'm lookin at =

http://www.tirerack.com/tires/...eTred

 

Besides the minor speedo error, here are some other changes (which are all very minor too, but depending on your needs may be important):

1) That much less tire tread to fender clearance in the wheel wells. This is only a problem if you are lowered a lot, need space to use chains, etc. Although a 185 is narrow enough to tuck in the wells if necessary. So then the only time you'd have a problem is if you run really low numerical offset wheels (pushing them outwards towards the fender lips) for some reason.

2) That much higher ride height (frame to ground).

3) Slightly taller gearing. This is a toss up, slightly slower acceleration through the gears, but lower cruising rpms/better mileage.

4) Slight loss of acceleration. Since the tire is a larger O.D. on the same rim, there is more mass and its farther out making it harder to turn.

5) If the old tire/new tire were the same model/construction, the taller one would give you a softer/more comfortable ride.


I did notice when I did the math, I came up with a slightly higher difference though. I got nominal O.D. values of ~22.74" and ~24.19 for ideal 185/60/14's and 185/70/14's respectively. That chart you posted lists that tire as being actually 24.3". Most 185/60/14's are more like 22.8" anyway, so that's 1.5" difference in O.D. giving you more like 3/4" sidewall difference.