I thought the same thing too, but then when I think of the 25gpm pump beeing in the rear of the car and pushing the water to through the IC then to the H/E that it would help get the water back to the trunk. I could be wrong, I just thought it may be needed. I guess it all really depends on the power of that 25gpm pump.
well I believe th eguys using a Meziere pump #136 is all they are using and thats a 20gpm pump.