Got an E plate sapph changed the head as the old one pitted on the gasket face so . Gp A gasket was fitted also.checked all the timing lined up off the workshop manual etc . Can never start it of the key only when i tow it even then it pops and bangs and sonds like its running on three. ive fitted New motorcraft plugs collins leads , rotor and cap ,new phase sensor gapped corectly, fuel filter . all plugs are black when i checked them its driving me up the wall any help would be a great as there is no cosworth specialsts in my area