it is the exact science of careful measuring, machining, balancing, fitting and testing. What I've done specifically to the C-rail has already been described in a previous post.

Since I'm running a blueprinted/CC'd intake manifold & combustion chambers as well as blueprinted & balanced injectors the blueprinted fuel rail seems only fitting. Like anything/everything mechanical, fuel too can only be delivered, distributed and as-well balanced as it's most unbalanced individual component.

No way the 034 AAN adapter will work with an AAH/AFC engine in the B4. It "may" work on the C-chassis cars. My fittings were CNC'd specifically to be identical to the 12V fuel rail ID/OD for silver brazing and and 1/8" NPT fuel gauge adapter thread which is pretty much standard on most, if not all mechanical fuel pressure gauges. Additionally I wanted the pressure to be taken half-way between left and right cylinder/injector banks "midway" in fuel rail's length rather than at inlet/outlet only.