Originally Posted by
Waterlogged
It's an easy enough assumption to make when one studies the design of the 1080.
[rambling post] There are 30 rows of copper tubes that run the length of the rad for the water to flow through. Now, both the in and out fittings are on the same end of the rad which tells us that it's either a 2 pass or 4 pass rad, to determine this, we only need to look at the number of plenum chamber caps on both ends. On the 1080, there are 3 on the end with the fittings which means that you have one plenum chamber for the inlet fittings, one for a 180º return pass and the third for outlet fittings and we have 2 plenums on the other side for 180º returns. This setup makes it a 4 pass rad. Now, we go back to our 30 rows of tubes, we can't divide this evenly among 4 passes so this means that 2 passes must be different than the others. Again, we go back to looking at both the plenum chamber caps (at both ends this time) and the amount of tubes per each cap. On the inlet, we see a full count of 10 tubes, yet at the other end (with only 2 plenum chambers) we see 15 tubes per plenum, this means that 5 tubes only return coolant to the end it came into the rad. This will offer a substantial restriction to the loop which will be furthered doubled due to the fact that the coolant has only gone half way through the rad. It still needs to go through another 180º bend, another 5 tube run, another 180º bend until it can get back to a 10 tube run and then out of the rad. With rads like the MCR, we have balanced flow throughout the rad, and even with 3 in the same loop, the pressure drop would be a bit less due to this balanced flow (that and they're just a better flowing rad to start with).[/rambling post]
Hope the ramblings of an old man made enough sense to help you sort this out. :rofl:
:welcome: