If you are thinking about getting an even bigger cam than a stock 240's, there is a youtube video about an owner who ran a Nismo R4 with stock compression ratio:
http://www.youtube.com/watch?v=JKTKf078 ... KRfQaCLch8 It has a mean sounding, lopey idle; but he changed the cam back to stock because it lost 15lbft of torque and gained only 5 peak horsepower. I'm not sure what other people have to say about it, but I think the compression might need to be raised as cams go bigger or else the difference will not be overwhelming. Since larger cams with more duration always reduce dynamic compression relative to static compression, you need more static compression to bring the dynamic up to where it needs to be.
From what I understand a stock 240sx cam is 240/248 and a stock truck cam is 232/232, not sure about the lift specs. I have heard people say that there is no difference between them, and then I hear that there is, so I'm just putting that out there. I know I never had a chance to compare them side to side or measure them. Nismo says the R4 has 270 duration on the intake side, but they don't say about the exhaust side. I think it might be a 270/270, but it still has way more duration than both stock cams.
I got to admit, our Nissan camshafts and lifters must have awesome friction surfaces. This is not the first time I read about someone swapping in a used cam that works out great, even using the "new" cam with their stock lifters.
