Whats the correct anti-freeze mixture ratio? I thought i heard it was something like 50:50 or 70(Water):30(Antifreeze) but im not sure.It doesnt say what ratio to use in any of the manuals I have .I do know that the v8 are dependant on the anti-freeze since they are aluminum.

In finland 50:50 is pretty much required as the temperatures can go much below -20celsius sometimes in northern parts. 70:30 should be fine for your climate.

An old leyland mechanic told me never to put neat water in as a top up and go for a 50:50 combination of anti-freeze and water, but as in the above post I can't see anything wrong with a 70:30 combo. I guess the point is to have a good mix before it goes in as the leyland mechanic said putting in water seperately could cause airlocks.

Ramon has a useful sheet on cooling system airlocks I think on his page

Think I better flush my coolant system out ASAP then, god knows whats in there at the moment!