I have been having, what sounds like a pinging noise on my 72 CSi that I have the 3.5 engine with the D-Jet. I have been told many things from bad bearings to a bad rocker and bad wrist pin and so on. Today I took it to another shop (Autobahn) and he told me that it is the cam that is the wrong type for this set up!! He said when the engine was changed, the cam from the Motronic system cannot work well with other systems and they should have also changed the cam and put in my original CSi cam in there. Can anyone confirm this? And if true, what other cams should I use since I don't have the old head anymore? Thanks.