Eric, In my humble opinion, your best bet is for a engine rebuild.  The
bottom end of the 2.1l motor tends to get tired by around 150k miles.  By
175k miles money should be saved up for a rebuild before one of the rods
decides to come out and visit.
So, to me, your best bang for the buck would definately to go with a rebuilt
motor.  That way you would have a nice, tight bottom end, topped with some
nice new heads and be in good shape for another 150k miles.
I would call Bob Donalds (www.bostonengine.com) and talk to him about a new
motor.
Hope this helps you.  This is only my opinion.  Worth as much as you paid for
it :)

Thanks,
Ken Wilford
http://www.vanagain.com
John 3:16
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