It wasnt cheap but it was accurate. i managed to get some very accurate (.001'c) probes from a lab supply company in france, i had a cut down temp probe glued against the side of the core with thermal adhesive as well as two air flow and temp sensors stuck in front and behind the rad, i had some water temp sensors salvaged out of a laser cutter from my dads work that handily went straight into a seriel port, they were siliconed into the line between the block, rad and pump and a flow rate sensor fed into the T-line so that i could work out any pressure change and thus take pretty much everything into account. Most of the things i tested were just tested against each other, i would use the same loop just switching the product being tested and noting the difference across the sensors, i ended up getting quite anal about it even waiting several days to get the right room temperature for mesuring the air differential in my dank little cellar.
Ah, the days when i did things with both halves of my ass
But of course, who takes the teenage hobbyist seriously when compared to a large company even if its only dipping its oar into a pond it knows nothing about.
This has lead me to other thoughts - what if this accuracy was what caused the difference in results, maybe it was the manufacturer who was incorrect in the first place and my findings merely made them look worse than even they thought they were.
Still, the site owners lack of commitment is probably what saved my ass from a courtroom thrashing all the same.