Working on it at the mo fer racing
(whilst at same time trying to get the "no coolant additives" rule lifted - cos I'm sick of the state of my radiator after a season... oldfashioned ruling that's stayed around FAR too long cos no-one's pointed out to the committee etc that there are coolants out there without glycol - but know their immediate answer - "but how can you tell what it is they've got in it" ie: that they're using a legal coolant, assuming I manage to get all non-glycol based corrosion-inhibitor only coolants allowed - can get it swayed if can find a quick cheap way to test for glycol presence in coolant)