I have a used BBK high pressure regulator and the BBK high pressure fuel rails for a 4.6 mustang gt etc . They work fine I swapped to a Different motor can’t use
The range from lowest setting PSI to highest PSI under full throttle was only about 7-8 PSI, while non-adjustable original equipment regulator would go up 10 PSI at full throttle. Looks nice but that's it. Wasted my money.