Thanks everyone!
One point I don't think I emphasized enough was that the higher durometer tubing really requires a lot more force to bend into such tight bends and therefore will place a LOT more tube torque on your blocks than a softer tubing. This is critical on blocks like the MCW-30 with only 2 mounting points and a relatively small base.
Mord, Cathar has a great article in the sticky section on the subject of tube sizes and flow rates. I think you will be surprised with the results.
Bookmarks