Jago hatte mir den Link gegeben und es deckt sich ganz gut mit dem Verständnis meiner Recherche...
Aus Preludezone:
„With the exception of a few oddballs, including the H22A, most Honda engines use cast-iron cylinder liners. Unlike cast iron, FRM is a metal-matrix composite made from carbon fiber and aluminum oxide, both high-end materials. The benefits of FRM as opposed to cast iron include improved heat transferring from the cylinders to the water jackets, higher wear resistance, and less weight. FRM allows designers to keep engine package and cooling system sizes minimal since heat-transfer properties are better, but Honda didn't exactly do that with the H22A. Instead of making the block smaller, which would in turn decrease the cooling system's jackets and port dimensions, Honda kept it the same, which means FRM-lined H22As are potentially more efficient in terms of cooling than cast-iron-lined engines, which means, in theory, they'll last longer. FRM is ceramic based, like spark plug insulators, so it's more durable than cast iron and theoretically has a longer service life. Theoretically. There's nothing wrong with FRM liners, that is, until you get into a buildup, and even then they're not so bad. The problem lies not just with the liners but the pistons. Honda developed special gravity-cast, aluminum-alloy pistons with specific expansion rates that work in an FRM environment. FRM liners expand more than cast-iron ones, which means the pistons have got to account for the expansion. Most aftermarket forged pistons are manufactured for use with cast-iron liners, which means popping a set in an FRM block can spell serious problems. None of this is really that big of a deal anymore though. A few piston manufacturers offer FRM-compatible forged pistons and ring sets and, if that doesn't float your boat, you can always sleeve the block with ductile iron sleeves, which you'd end up needing anyway if you're shooting for big numbers.„
Nicht klar von wem diese Antwort von einer User-Anfrage kommt, aber sie klingt logisch.