Do boat engines count for this thread? If so, the Mercruiser 3.7l 4cyl "470" in the boat I sold a few years ago. A Frankenstein nightmare of Ford, GM, and Mercruiser voodoo all cobbled together for tons of fun. Four pistons and the iron head from a Ford 460 big block, mounted to an open deck home grown Mercruiser aluminum block, driving a crank taken from a tractor (I forget what manufacturer), fired by a GM marine distributor, topped with a Mercruiser-modified 4 bbl Quadrajet, with an outboard style permanent magnet and carbon pile charging system capable of boiling your battery in minutes when the water-cooled voltage regulator inevitably failed. All cooled by an internal beltless water pump with its impeller mounted to the end of the camshaft that had a horrible habit of corroding and dumping the antifreeze into the crank when the corrosion chewed up the seals.
It was a seriously torquey beast that sipped gas and pulled like a dang freight train, and in the right hands...someone who really studied and knew the engine, who loved tinkering, had a habit of way over-maintaining things, like modding things and had gasoline in their veins and a lot of tools, it was a fun, reliable, very powerful engine for a small or midsized boat.
In the wrong hands, owned by someone not too mechanically inclined and who liked to skimp on maintenance, it was a horrific money pit of misery, depression and despair that would leave you stranded dead in the water and take every penny of your next four paychecks for endless new head gaskets, warped blocks, leaky water pumps, antifreeze fried bearings, and a burned up charging system if you dared to even glance at it with the wrong attitude.
