Postby belalegosi » September 14th, 2012, 4:01 pm
IMO for a stock & mostly daily driven car, I would just run decent coolant.
Nothing fancy is really needed if you cooling system is functioning properly.
I've always just ran regular (read cheap) coolant and I beat the living hell out of it all year round (-40C to over 32C).
Interestingly enough, engines make more power being ran hotter. Having a cooling system "work too good" robs the engine of valuable heat. Also for modern EFI engines, if the coolant temp goes too low, the engine management would engage warm up mode ie running richer and robbing you maximum powaaaaaaa