The V8 Owners Forum -

My system is not as above. All my TVR donor had was the one expansion tank with blue (VW) pressure cap on it. The rest was a closed system so expansion forces water into this tank via shown tube and sucks it back when cooling down. (I can also vouch that when pressure got too high, the blue cap allowed water to blow out!)

I have had good results from my system. It is definitely the most work, but it is 'fit and forget', rather than 'fit, then just check it's bled, then worry on a hot day as to whether air is building up etc etc.' !

Just my two pence worth.

Chris.