I think what you're referring to is Evans NPG.  We have to run it in the Eagle540 because of the magnesium heads and intake manifold.  It's a bit pricey, at around $25/gal, and if you've had 50/50 water/anti-freeze in the system you need to 1) flush & purge the system with clean water, 2) drain well and blow out with air, then 3) use the Evans "purge" fluid that binds with the last of the water in the system.   4) Drain that and fill with NPG.  We had to send back a sample of coolant after the first engine run to verify that 99% of the water had been removed prior to filling... we did ok.  What seems really strange is to have a recommendation from Evans that says to use a zero psi cap... although they did say it's ok to use one up to about 7psi if you really need to have a pressurized system.  Interesting stuff.

    <Marv>



<daveleonard@cox.net>:

One of the guys at the airport says that "all" the subaru guys are using something called MPG instead of Ethylene Glycol/water because it boils at 290 without need to be pressurized.