So I figure:  top o' the green is 4000 RPM.  That shows
as ~71 mph on my speedo, which reads high.  I think it
is really ~65 mph.

So running at the top o' the green on the tach is 65.

Do people drive faster?  Do they run the engine at
higher RPM?

I know in my air-cooled, with NO tach, I just rev it
up!

                        Richard A. Jones
                        Boulder, Colorado
                        '81 Vanagon   Mr Bus
                        '87 Syncro Westy   El Jefe