The air-cooled flat-six that fills the rear of the early Porsche 911 is a motor so revered that a debate over the decision to move to liquid cooling can bring fans to the verge of fisticuffs.
So, what about 38 of them, racing wheel-to-wheel at the Spa Classic? Not the worst proposal in the world we might suggest.
That's exactly what the 2.0-litre cup is, a series for just air-cooled early 911s, taking place at each of Peter Auto's events across the European summer. And the treat here is that these near perma-sideways beasts will be taking on some of the most fearsome corners in world motorsport.
If you don't like 911s, probably best to look away now. But, if you appreciate the lines of that iconic rear-engined shape, and especially the un-adulterated early design, then this is a gallery for you.