Karl, I've been pondering the same question with my 82 1.9n/a. AutoTech, who
sell oil coolers for HiPerf Golfs/Jettas, advised that with a large cooler
like I had (8"X12" flat plate) that it would not be necessary to run it up to
the front of the radiator. They claim it would act as a heat sink even if
mounted out of the air stream and that if more cooling were needed to use a
small motorcycle 12v fan and a thermistor (there's that word again). I read
in the old How to Hotrod Your VW book that you should NOT use a/c condensers.
I think I've also read in the archives about people having used them with no
problems. I think I've also read in the archives about a 1.9TDI that
maintained oil temperatures without going to aux cooling. I have the stock
oil-to-water cooler and my temp goes as high as 270F. AutoTech suggests I
remove the stock cooler because of leakage problems they've seen. I would
prefer to keep it but I'm also going to use a thermostatic "sandwich"
adapter. If I use the stock cooler+adapter I have to use a shorter oil filter
to clear the hose from the waterpump (I run System 1 oil filters). I'm just
throwing all this out in hope of finding answers for both of us.

Ken Hunter
82 Westy 1.9n/a