I agree that the cam timing should be checked again. Especially since the machine shop had problems with your timing chain. As I posted on the first page this sounds way too familier to what I had when I assembled my 360's timing chain a tooth off.
I was also told by edelbrock when I called them before finding the chain off that if I installed a cheaper timing set that some manufacturers machine the timing sets to be 2-4 degrees retarded for emisions reasons. Edelbrock told me that if I pulled the front cover and it was lined up correctly that the issue lies in an "emmisions timing set".
