‘Round these parts, we love straight sixes. But they can sometimes be regarded in America as outdated, low-tech beasts (except for BMW fanbois, of course). But the inline-six engine has progressed over the years into something as advanced and sophisticated as any other internal combustion configuration, including the use of dual overhead camshafts. In fact, DOHC inline engines have the advantage over vee engines in weight, cost and complexity, since the cam drive apparatus does not need to be duplicated for two separate heads.
So let us celebrate the DOHC straight six by compiling a comprehensive list of all the different iterations of this configuration.
The Caveats (there are always caveats):

• We are listing engine designs, not cars. The number or variety of different vehicles an engine ended up in doesn’t matter.
• Conversely, different generations count separately. If it’s got a new block or new head casting, it’s a new entry.
• We’re looking for mass-produced, road-going engines. No grand prix works specials.
• Diesel and petrol are both allowable.

Difficulty: Medium Hot (as long as you don’t bite into the jalapeño seeds).
How This Works: Read the comments first and don’t post duplicates! Bonus points for adding photos.
Image Source: counterman.com and Wikipedia.