About fuel quality, here in New Zealand we get any crap. It is actually so bad that a few manufaturers (Ford comes to mind) do not import their latest model with direct injection, because the sulpher content is too high for the engine. It's an interesting engine that lowers the mixture and change timing and ignition under low load in such a way that most of the mixture is high up in the cylinder at the plugs. This way the average mixture is lean, but where ignition occurs it is still correct. Anyway, these engines will not run on NZ fuel, so there are manufacturers pushing for fuel standards. Currently the sulpher content spec is 500 PPM (parts per million) max, where as other countries are 50 PPM and pushing for 15 PPM. (Please do not quote these figures as I've read this a few days ago, but the principal and ratio is correct.) Not that any of this affects us that much other than that fuel quality worldwide should increase as green cars require it.

I use Mobil Synergy 8000 unleaded which is supposed to be 98 RON, but my manual specify 100 RON minimum. This is for a B20B. Back in South Africa we could still get 100 leaded, but I think that is running out as well. I still remember the days when 110 was available... LPG is around 105 which works nice on a high compression motor.