Exactly my point KSW!
Would not a slower flow rate throught the rad. work better than a faster flow rate?
Then we come up to the catch 22.....
How do you keep a high flowrate into the waterblock yet keep the flowrate slow in the radiator?
I think my setup kida allows for both to happen, just by how it is configured (Res. at the top feeding water to the pump at the bottom)