Viscous fan performance

Im just wondering, purely for knowledge purposes, does anyone know the CFM of the stock Toyota viscous cooling fan? A pair of lectric replacements can flow over 2000CFM

TIA

I think it was calculated somewhere here a while ago and the flow was about the same. The viscous fan being preferred as they are cowled. However, unless you have a current overheating problem, it's pretty much pointless changing, isn't it?

I know the shroud makes a huge difference to the efficiency of it, Ive got an Aristo which has the same fan but a crazy hydraulic power unit combined with the water pump. So when the pump goes whats best, Supra pump and viscous fan or electrics.

As I said its purely hypothetical

Supra pump and viscous. I run big HP RB26DETT engines with a direct fan drive, no viscous. Noisy, uses a bit of power, but stops overheating issues on track. Electric fans are very rarely a good option on big HP, big capacity engines, nor is removing the shrouding and ducting.

I'd love to know the thinking behind the hydraulic-drive fans. It seems like a really complicated solution to a non-existent problem.

Toyota used them on the first generation of the 1JZ (Mk3 Supra) and 2JZ (Aristo), then abandoned the idea in favour of an ordinary viscous arrangement on the Soarer and Mk4.

Since the viscous fan seems to be more than adequate, why on earth did they design and engineer such a complicated system?

Some Chasers also run the hydro setup. If i was going to do anything it would be to convert to the Normal Viscous setup, as gareth says its one of those "why on earth" things toyota implimented, and can be a ball ache when it goes wrong.