Kind of late to the game here, but 240's are a great platform and the KA24DE is actually very robust, reliable, and very simple to work on. Piston oil squirters, shim over bucket valve train, timing chain, 9.5:1 compression ratio, etc. The problem is when people drive it like it's a Honda I4 that makes all it's power at the redline. Factory redline is 7k RPM and no one should be shifting anywhere near there because anything above 6200 RPM is just noise. They are torquey (160 lbs*ft @ 4400 RPM, 155 bhp @ 5400 RPM) and should be driven that way and more than hold their own against higher output Lemons cars.
Even though lap times should be the least of your worries in Lemons/endurance racing, the 2 races our 240 was alive (it was totaled in only an hour in it's 3rd race after resolving a fuel pump issue), it recorded the 6th fastest and 2nd fastest times of the weekend (NJMP 8/2013 and New Hampshire 10/2013). The platform has already won a couple of Chump Car races so it's only a matter of time it'll get the overall win at a Lemons race.
But, like others have said, the Dorifto crowd has inflated prices to a laughable point for even the biggest POS's. Rust on the frame rails and rocker panels is almost always an issue in the snow belt at this price point. There is obviously a lot more to talk about, so you can email me if you'd like.
Team Failken: Formula D-Bags: #14 93 Nissan 240sx
Team Pro-Crash-Duh-Nation: #26 '87 Alfa Romeo Milano