Anyone run 215/70/14 on 14 x 5.5 rims

to calculate your speedo change, all you need to know is the diameter of each size of tire, then convert the difference to a percentage and that is the percentage of change you can expect from your speedo.
in this case, a 215/70/14 tire is 4% larger than a 195/70/14. so you would actually be travelling 4% faster than what the speedo reads. so at 50mph on the speedo you would actually be going 52mph. at 25 on the speedo you would be going 26, at 100 you would be going 104. just remember its a percentage not a set number of mph.
brewer's has a whole bunch of speedo gears and if you tell them what tire size, rear end ratio, and final drive (most likely 1:1 unless you have an overdrive tranny) they will be able to find you a speedo gear to correct for the taller tire.
-Tim