I don't have  much Vanagon experience. But there is a conversion I've
seen in Germany, I really liked: 2.2 (I believe) TDI. That's the big
TDI engine (you know the Passats, Audis and Golfs with the red "I"
in the TDI script). Very fuel effcient, lots of bottom end torque and
it's a VW engine, too.

Marcus

74 Westy with 914 2.0
79 Westy
84 Vanagon GL