Myths & Rants, Part the Second, Wherein One of Ludwig's Drivers Attempts to Demolish a Bit of Conventional Wisdom about Air-Cooled Volkswagens: The Bus with the Porsche Engine

Myth: Yeah, I used to have one of those VW buses with the Porsche engine in it.

Rant: Probably every bus owner has heard this line at least once, usually from some stooge who comes strolling up to them in the parking lot at KMart. But sadly, it just ain't so.

this one's a fuelie

Variations on the 1700/1800/2000 cc engine--commonly though somewhat mistakenly often referred to (including by yours truly) as the "Type IV" engine--were installed in...

...the VW 411,

...the VW 412 (and what a lovely pair of monsters those two make), 

...the Porsche 914-4 (tellingly, sold under the marque VW-Porsche everywhere except North America), 

...the 1976 Porsche 912E, and, of course... 

...1972-1979 VW Type IIs (buses) bound for the USA, like this one. (And, I should add, 1980-1983.5 Vanagons.) 

The temptation to mention these lofty Porsches as they relate to the lowly VW bus is too much for some to resist, so the connection gets strengthened and offered as some esoteric, wildly counterintuitive fact. Those perpetuating this myth are typically the same kind of people who insist that we only use 10% of our brains. 

that's not to say there aren't a few genuine Stuttgarter powerplants hidden under Wolfsburger clothing; don't try this at home

The boring old truth is that the blame for the 1700/1800/2000 engine belongs to VW. Sure, the VW and Porsche engineering camps were plenty incestuous in the 1960s (when the engine was designed), and Porsche helped VW with it just like they helped VW with everything, and vice versa. But you don't think a Beetle has a Porsche engine in it simply because a Beetle's engine and a 356's engine were dreamed up by the same guy and look a lot alike, right? Right.
Porsche significantly tweaked the 1700/1800/2000, mostly in the cylinder heads and cam I'm told, before installing it in either of their cars in any case. Those details were incorporated to push a slick little 2,100 lb. 914-4 down the road, and aren't at all appropriate for moving 4,600 lbs. of bus around. You know, in case you were gonna try it.