Tend to find the 0/40 is too thin so will aim for the thicker oil at next change. Plugs are usually set correctly, but halfrauds etc couldn't get me any 6 months or so ago. Track-car solutions sorted me no problem though..
When TVR first recomended Mobile 1 it was 10/40 or 15/40, but is now 0/40 and that's just too thin. 10/50 or 15/50 will be fine. also its recomened to change every 3000. see the oil sticky in general TVR. Also all new plug come with the correct gap so should not need adjusting.
