[77newell]

I've thought about this route for my 93 with the 8V92 with rear radiator in order to reduce the power consumed by the single big direct drive fan. The design would involve some kind of controller that would stage multiple fans just as Prevost has done based upon some engine parameter such as engine power and/or coolant temperature. I've noticed a lag between increased engine power and coolant temperature rise so coming up with an algorithm that would kick in additional fans as power increases, assuming the engine is near operating temperature, would reduce the need for even more fans if we wait until the coolant temperature rises.

I've noticed the current radiator fan design is less than optimal with part of the fan outside the shroud and with the shroud doing little to distribute the air evenly over the radiator surface. This less than optimal design is due to lack of space behind the engine to install a more efficient shroud which would be longer than the current shroud.

While the electric fan design reduces power required to force cooling air through the radiator, it does not eliminate the drag on the drive engine completely if/when the electricity is produced by an engine driven alternator.

I'm still interested in the challenge of getting my coach to average above 7mpg and the cooling system is definitely an area of opportunity.