danger den rbx test at overclockers

[Cathar]

Originally posted by bozo
the test has been updated, puts the RBX at a c/w of 12

Really? I saw 0.132

...and he still used an Eheim 1260, giving the strange results of the block having a higher pressure drop than the PolarFlo, but also receiving higher flow rates than the PolarFlo, due to the 1260's better ability to deal with pressure drops when restricted.

i.e. JoeC is reporting different points on the pressure vs C/W curve as if they all correlated and were equal. Not saying that the difference would be dramatic, but he has slightly biased the results against all the other blocks he's tested to date.

One would predict flow rates of around 0.85GPM if he had used the 1048, which may correspond to a ~0.005C/W difference, or enough for JoeC to report a 0.14C/W value instead.

Very curious measurement methodology that he has going on there.

Maybe BillA might like to have a word with him about what he's doing.

[bozo]

why didnt he post results of the block on all 3 pumps?

[jaydee]

Originally posted by bozo
why didnt he post results of the block on all 3 pumps?

Ummm, more like why isn't he using one big pump and regulating the flow rate with a valve and taking results at different flow rates to create flow vrs. c/w curve....

[Cathar]

Originally posted by jaydee116
Ummm, more like why isn't he using one big pump and regulating the flow rate with a valve and taking results at different flow rates to create flow vrs. c/w curve....

Yes, as it stands the results with the Eheim 1260 have marginal correlation with the results of the blocks with the Eheim 1048, but JoeC doesn't mention this.

The RBX has 4x the pressure drop of the SlitEdge, but is receiving the same flow rate as the SlitEdge due to the 1260 being used.

Again, not a major deal, but if JoeC wants to compare apples to apples using his chosen measurement methdology, then he really should be aware that he's just gone and slanted the test towards the RBX, and away from the other blocks tested.

[leejsmith]

i have mailed joec asking if he also tested the rbx with the 1048 or to use the 1260 to test all the other blocks to.

the mail also asked the question of the pq curves of the to pumps and the 1260 having higher head pressure and giving better results than a 1048 when both are restricted to 1 gpm.

just have to wait

[BillA]

JoeC will need feedback from the 'general public' to appreciate his 'confusion'

mixing pumps is not good at all
and the rounding to hundredths is showing greater or lesser differences than actual