I just purchased a C8 2.2 petrol 2004. The cambelt tensioner failed apparently at 15 miles an hour. Previous owner sold it to me cheap. Seems to be everything on net about 2.2 diesel engine but nothjing about 16v petrol. With the diesel engine valves parallel to piston so breaks rockers aparently I am assuming petrol engine probably more damage and probably engine rebuild, about to remove head any advise would be helpful. Possible damage wise etc.