i have always used the raceline water rail on my zetec and in all the yrs ive had it the cooling on the car has never been right. ive suffered from over heating and overcooling more so sense i supercharged the engine, i wanted the cooling to run at approx 90deg but could never get the raceline to do it temps would range from 120 to 80 due to the thermostat being located to far from the head.
So i try the davis craig electric water pump system, intially it was very disappointing but after discussions direct with manufacturer they came up with a solution which with the raceline wouldnt work properly.
i get a retroford water rail and find that its not quite a direct replacement needing a coilpack bracket making and the dipstick moving slightly, not a bad thing as this gave me the chance to make a custom bracket for the coil and fuel pressure reg that had always been mounted in a temp fashion. once fitted up with the EWP the car now has quick warm up and and stays close to the target 90deg.
the ultimate test was on the dyno yesterday, the car maintained target temps on the dyno, probably the harshest teat you can put your car through. the dyno operator even commented on the fact the car maintained temps perfectly.
so raceline v retroford retro is better in my situation ( it works)
Davis craig EWP and digital controller, great bit of kit that that does the job well, but dosen't as claimed give you any BHP increase...(in my case anyhow)