HI Neil, If you've got coolant spray down the RHS have you checked the top rail is secure into the alloy housing, its a bit like an angled socket, my CSR200 rail popped out of its socket spraying coolant every where...the bracket holding the rail wasn't sufficient so they installed a clamp used on the 620r, all fine now!!... Just a thought Zircotech is interesting i was going to wrap my headers!!..did you try wrapping first? Best StEVEN