I would kinda of agree with Alex after tracking at Silverstone last weekend with it being a warmer day, the water temps did rise and the engine was running about 10 f higher than normally. Thus being caused by a hard workign turbo sitting an inch away from the rad.
I have two fans constatnly running on a huge pro alloy rad up front.

I would however think that if rad in the back if airflow is sourced it should run so much cooler as there is no heat around it whatsoever.

I have emailed mdv who built Dorans cars to see if they can shed any more light.

I need to look closely at the doran cars hopefully they will be at national day.

I thought the scoop on the roof was for driver comfort