>One small tidbit: apparently the 5 cylinder
>engine in the Audi GT (perhaps the Audi >80
>too?) had a "closer fitting" intake manifold
>than the 5000/100/200, due to the >smaller
>engine bay/hood, making it a better choice
>for a Vanagon transplant.
That's not true, the intake manifold  on the
Audi 80/4000 is to be fedded on the rear, that
means opposite of the firewall in the Vanagon.
If you don't cut the whole firewall, it would
not fit. There is enough space for the 5000
engine, if using parts of the rubber tube of
the 4000. It is recommended to use the air
cleaner box of the 4000, too.

Helmut
'80 Vanagaudi