Fuel line? Is it enough

Spanky - with all that rubber you have a fire hazzard there... The three tracks I run wouldn't let you run the car like that.

"Not doubting you but I am curious to how a return line restriction adversely affects fuel pressure?"

A bypass regulator is made to regulate a circular system without a restriction on the return side. If the return is too small the regulator "feels" the backpressure and does not do it's job accurately or very steady. The return should have the same capacity as the feed line to use a bypass regulator effectively and the pump and lines should have extra capacity over and above what the engine requires afor volume at peak power. How much more capacity is dependant on the fuel, the size of the lines, and the overall perforamnce of the car.