So, the way I'm reading the chart you posted, the OEM pump is 4 GPM and the Johnson CM30 is a 6.9 GPM. Now the big question is, will pumping an extra 2.9 GPM thru the S/C system help in performance. I would hope that the MB engineer's knew what they were doing when they went with the 4 GPM pump on the car. But the car is no longer stock with the bigger pulley. I know there is a point to where you can pump the coolant to fast and not have time for the radiator/heat exchanger to cool it. I found this out first hand with my old Mustang when I put 3:55 gears in the rearend and had to change them back out for some 3:25's to get the RPM's back down at highway speeds (wasn't able to slow down the water pump with pulley's). I know there are a lot of people running the CM30 with no problems, but did they check the difference's in temps before and after changing pumps? You probably have some first hand knowledge of this, so what's your opinion here on this HDDP?
Thanks, Steve