QUOTE(bob91403 @ Oct 20 2004, 01:19 AM)
Has there been any statistics on how long the average one lasts? And, if it's so great, why isn't mazda using it in all their cars?
the consensus in the racing works when they were The Hot Shitte in IMSA was that they'll last pretty much forever - but in time they develop so much internal friction that the power output goes way down.
they aren't more popular because despite their lightness, simplicity, and legendary mechanical efficiency, they have horrible thermal efficiency due to the very large surface area of the combustion chamber. this results in relatively poor fuel economy, problems making emissions numbers, and challenges for the cooling system to reject the heat.
they also tend to be loud, and noise standards the world over are getting more and more strict. (to the point where no new air-cooled Porsche could be sold into Switzerland -- this is one big factor with the water cooling in the 986 and 996.)
i drove an RX-2 for a while, primitive 4-link + Panhard rod rear suspension, dead shocks, balky transmission. would rev all day long if you could ever get it started. it eventually got T-boned in traffic and i no longer had a reason to follow them closely...