Liquid Flow Restriction

I use a Swiftech MCP50X pump with a FrozenQ 400mL cylindrical reservoir. The pump is powered by a direct SATA connection to a CORSAIR HX750 PSU and controlled by an Aquacomputer Aquaero 6 XT. There is a previously calibrated in-line flow meter and Dwyer 490 Series 1 wet-wet manometer to measure the pressure drop of the component being tested—in this case that of each radiator. Every component is connected to the manometer by the way of 1/2" x 3/4" tubing, compression fittings, and two T-fittings.


If you have read through the previous page, these results won't surprise you. The dual row of comparatively thin tubing ultimately strikes a balance wherein the Heatkiller Rad 360-L is more restrictive than other dual-row radiators in the same thickness class that either have thicker or more tubes per row, but the Heatkiller Rad 360-L is also far less restrictive than the Black Ice Nemesis and its OEM versions that use even thinner tubing. The single-row Heatkiller 360-S fares worse given the smaller parallel split with 12 tubes vs. the 24 here. Overall, I would still term this a low-restriction radiator, but only just. An average CPU or GPU water block comes in much higher. Note also that these results are taken at 1 GPM coolant flow in order to relate to historical measurements, but you really don't need this high a coolant flow to reap the cooling benefits of custom watercooling.