> We have an ABA conversion with 1.8 heads and Digifant II in two of our Vanagons.
> From a maintenance perspective the I4 is easier to work on. Everything is accessible. Timing belt jobs are easy.  Aftermarket higher performance parts are still available. The heads don’t piss on your driveway.  But you better have a solid, professional conversion with a well-built exhaust that is properly hung off the engine or has sufficient flex sections.
>
> Down side of the I4 is the soft torque at lower revs. On the flip side it redlines at 6400 rpm and I hit 78 mph in 3rd gear. They love to rev.

I second all Chris's comments on this conversion.

Running premium gas helps noticeably with the torque at lower RPM (as
well as MPG) due to the knock sensor and high compression.  I haven't
been able to compare to a stock engine, but the power seems totally
reasonable for modern driving.  Aside from the exhaust, the other pain
point specific to this engine (using the the original diesel oil pan
and bellhousing) that I've experienced is a failure of even a new oil
pump to prime reliably unless the end play been specially clearanced
(wet sanding and plastigauge), as the pump seems quite high above the
oil sump level.

Alex