Nathaniel,

The larger issue here is that you have predicated your questions on the
notion that you want to remove the 2.0l AC engine and put a Subaru (or
other water-cooled) conversion into your van.

This discussion of ring wear is largely irrelevant to that.  No one has
addressed this.

While a review of the archives of the subaruvanagon yahoo list will show
that a few people have done this successfully, it is a lot of extra work
and expense compared to doing the conversion on a van that already had a
water cooled engine.  The cost estimates that are typically associated
with DIY or shop Subaru conversions will be much lower than what this
project would cost you.  The whole cooling system, heating system, etc.,
would have to be created and installed in the van.  Most folks,
including some who have done it advise against it, suggesting that you
sell the AC vanagon and find a diesel or WBX upon which to base the
conversion.

Sam

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Sam Walters

Baltimore, MD