[Christ]

Yep, its gonna be obnoxious.

I you intend to run a single fuel system, get a used set of injectors for about $50 off ebay, clean, rebuild them to 140+ bar, within 1 bar of each other. You will need to make a $50 pop tester to do this.

In the pop tester, use whatever fuel you intend to run the car on. If dual fuel, use the primary fuel. The viscosity of the fuel affects the breaking pressure of the injectors. You want to set them so they have a clean spray/fog with no drips/peeing, and a nice pattern.

Your injection pump timing wil also need to be adjusted, and it will be hit or miss. Set it to factory specs, then adjust it to the best setting for your fuel from there.

For ULSD, 130 bar is actually quite sufficient, due to its very low viscosity. It atomizes with very little effort. VW raised the break pressure on the turbo models to 150 bar to ensure proper atomization of the old stuff under boost.

Lower than stock break pressure advances the injection timing slightly. Make up for it by changing the timing at the pump.

If need higher break pressures, again, adjust pump accordingly.

The more I drive my golf, the more I find out that it's almost the polar opposite of driving a gasser, in terms of fuel economy.