Hi all, my coolant is just water at the moment and need to add antifreeze. It's a 2.5 n/a (12j) and I'm after how many litres the whole system is all the way up to the header tank so i can mix in antifreeze. can't find the answer anywhere and Haynes is not very helpful. Or I could just poor "a load" in and hope for the best haha. Cheers.