While my '84 has no tachometer, I shift according to the
speedometer.

1st       10mph
2nd       20mph
3rd      30-35mph
4th      40-45mph

    I really drive my van like an old man with fidora on, but I always
maintain a cruising speed of 55-60mph on the highway and stick to the
posted limits on the back roads.  Not the case however with the TDi, if
there still is pedal it just has to go faster.

Jason Yasment
'84 Vanagon Westfalia
'98 Jetta TDi
hmmm engine swap......wife would kill me