High performance engine and tranny oil

Hi
Can anyone recoomend me a high performance engine and tranny oil for my 2110 engine and my street / strip tranny the car will be run in Queensland mostly, at the moment I am using Valvoline VR1 20/50 which I can't get in Australia according to the importer, only 10/40 is available ( not sure this will be good enough for the engine due to the hot conditions ), the tranny has red line in it

Daz