I asked about this and said:
> I'm thinking that 2.7-2.8% isn't much

I had two valuable comments.  One, by John Mayer with experience
climbing Monarch Pass with bigger tires and having to drop into
2nd more.  That's my concern exactly on I-70 at the tunnel, and
Vail Pass.  I already have to drop into 2nd in places.

The other by Steve Schwenk:
> But consider.  Do you really think the VW engineers left a "2.8%"
> cushion in there...or reserve of available power....or do you
> think they geared the 2.1 for maximum efficiency in terms of
> gearing vs. available power?  Do you think there is 2.8% fat
> in the gearing?  Or do you think they geared it as high as
> they could (3rd & 4th gears) given the available power?
He's probably right--they did think about it.  By the time of
the 2.1, they were dealing with an old tire size that they didn't
want to change for some reason, so they probably did just what
Steve says.

                                Richard A Jones
                                Boulder, Colorado