Where is that pic overkill? I wouldnt mind seeing it. Would you say Mobil 1 is my best bet no other synthetic or a Dino ?
This engine has 338,000Km's on it (210,000 miles):
10-12,000Km OCI's on various grades of Mobil 1, the last I used was the 0w40 when it became available. Prior to that it saw everything from 0w20 to 5w50.
Oil filters were K&N or Motorcraft.
This is a 1987 302 from my '87 GT T-Top. The rest of this engine is just as clean. I think the age is relevant.
I'm a bit like Tig (though not as long a time period) but have been using Mobil 1 since my dad started letting me change the oil in our Townie, which was 1994.
In every engine I've ever used it in, the results were always a clean engine.
IMHO, their 0w40 is their flagship product designed for extended-drain Euro applications. It is their most robust formula and subsequently is going to do the most cleaning. THAT would be my suggestion for this application. It isn't going to clean it up over night, but then, you wouldn't want it to. But it will clean it up.