Good article pg 70 comparing external engine temps when using  conventional
and synthetic.

The numbers show synthetic does a great job of cooling the engine.  I don't
like the conclusion statement though:  "Of course, the car now leaks because
of the viscosity of the synthetic oil, but I guess we halfway expected that."

I was all set in my mind to switch to Valvoline Synpower 20W50 until I read
that.
I have a type IV with 2000 miles on the rebuild and this would be a great
time to switch...

Paul
'82 Vanagon L Automatic