Radiator efficiency

Now that the engine build is underway its time to focum my attention on cooling the thing down.
There are a number of good deals here in the UK on Alloy radiators, but as discussed before the british summer has nothing on an Aussie one and they may not be suitable.
Is there a universal measure as to a radiators cooling efficiency that I could use to compare like for like between brands or manufacturers.
Who has experience with particular brands etc in Aus with a turbo cosworth engine.
If there is a universal measure should a manufacturer of a radiator be able to supply me with their design efficiency/rating?
Hope you can help
cheers,
JP
There are a number of good deals here in the UK on Alloy radiators, but as discussed before the british summer has nothing on an Aussie one and they may not be suitable.
Is there a universal measure as to a radiators cooling efficiency that I could use to compare like for like between brands or manufacturers.
Who has experience with particular brands etc in Aus with a turbo cosworth engine.
If there is a universal measure should a manufacturer of a radiator be able to supply me with their design efficiency/rating?
Hope you can help
cheers,
JP