I know while I'm competing in sprints you don't have heaps of time to spend looking at gauges; I'm looking at armco, tyre walls and for other cars..I don't think I would be able to hear a buzzer with an L28 with triples screaming at 6500 rpm. Ash, alot of people refer to oil lights as idiot lights and yeah, if it's on its too late!
But Simon, to be safe and not being able to run at an event just for that reason, just make a oil catch can of about 3 liters in capacity, bolt it in and enjoy a day of racing. I think this thread may go outta control!