So I guess that my cast-iron block with aluminum head and copper pipe to the
heater is not a prime candidate for distilled water? ;-)
I know that some racers run straight water with RedLine water wetter (like
PPP carries) which claims:
"Red Line Water Wetter provides corrosion and rust protection for modern
aluminum and cast iron cooling systems. A unique additive reduces coolant
temperatures by as much as 30 degrees F. This additive can be used in plain
water, to provide much better heat transfer properties and protection than
glycol-based antifreeze, or can be added to new or used antifreeze to
fortify inhibitors and reduce foaming."
As a non-racer, I stick with anti-freeze, but I might be tempted to add some
of this, too.
1972 RWA Midget