I did talk to the guy about the conversion but he could only give the name of the chap who serviced it - who I also spoke to. He said he didn't install it but the system was old (not a Prin (?) but something else and that it wouldn't be something he would do now as there are better system available - but I understand it has been regularly serviced). As to the Cambelt I really don't know. That reminds me I should get mine done