Beav, I find it hard to believe that in the land of a million petrol pumps that the octane numbers are so low. Here in Aust. the lowest ULP is 92, the premium is 95 and there is OPTAMAX which is 98RON.
The sticker under the hood of my 95 mod says minimum octane 95RON.
When I am doing a fast trip out west, I use 98RON, you can feel the difference when overtaking at around the 200kph(120mph), the top end is much stronger. The computer lets the ignition advance, to develop the max pressure and torque.
I bet it really drops it's bundle when running on 80 RON.
Wouldn't pull a greasey stick out of a pigs arse!
Harvey.