Octane Boosters

We pay $1.50 per litre of 98 RON fule here. When I've had to use octane booster, I use Nulon Octane Boost & Clean....raises the fuel 2.5 numbers......and it works......use whole bottle for a 60 lt tank.
http://www.nulon.com.au/products/Octane_Boost_and_Clean/

The old stuff used to raise it buy 7 numbers.....probably stopped making it coz it ain't good for you or the enviroment.....:(