> i have a question about fitting tires to wheels.  wheels seem to be
> specified based on a diameter and width, both in inches.  matching the
> former to a tire is simple, obviously, but how about the second?

If you have a 6.5 inch wheel, the wheel is 165 mm wide, since i inch is
2.54 cm.  Coincidentally a 165/70 15 tire will also have a tread width of
6.5 inches.  Logic would tell you that you probably don't want your tread
narrower than your wheel, correct?

Each tire manufacturer specifies a minimum rim width, and for a lot of 215
tires it is somewhere around 6''.  I would presume that with your 6.5''
rims you could install tires from 195 up to the maximum size allowed by
your rim width and the clearance between the tire sidewall and the tie rod
(this assuming you have a 2wd Vanagon) - So, shall we say, 195 to 225
tires with appropriate aspect ratios as to keep your tire diameter within
check.  The offroad crowd may opt for something a bit more extreme,
however, in which case you should consult an Syncro afficionado.

I myself am currently running 27x8.5 14 tires, which roughly a 215/75
equivalent, on the stock 5.5'' wide rims.  My tires are supposed to be
mounted on wheels at least 6'' wide, but I've had no problems related to
this, and I still cruise at 75mph.

Chris S.
'85 Wolfsburg Westy "Camel"
http://www.knology.net/~vw/dadada.jpg