Aw come on it was a joke!
Though it's not like they are really that different. They all have pistons, cylinders, and valves. If you want REALLY different you'd have to go to a wankel (rotary) motor...
In reality now I've been trying to source a new motor for my CJ7 Jeep and all of the used engine guys have been looking at me weird when I say "Which 5.7 Liter is that V8?"... I've heard "they're all the same" so many times. Never mind the difference in complexity between fuel injection and carbs.
I think I've decided to go with a 5.3L like what is in my Avalanche as a few companies are making the computers to allow that kind of install. It is also almost as light as the AMC 258 20 year old six cylinder in there now. Which blows my mind.
Engines really they are all the same.....
<--- see smiley?