I have a 1989 Silverado with a remanufactured tbi, new injectors, new Russell performance stainless line, an6 fittings, new ac delco fuel pump, new fuel tank and I'm only getting 6 psi at my Tbi. I have an adjustable fuel pressure regulator and new diaphragm and spring. When I kink the return line it jumps to 14psi. No kinks in the lines. Please help.

You should have 60 psi at the tbi, and 17-18 psi threw the tbi, Check that fuel pressure again, 6 psi from fuel pump it will not run. Do this first before adjusting the pressure at the tbi.

Bought new jet billet adjustable regulator and now I can maintain anywhere from 11-20. Keep in mind This is a tbi that is low pressure. The factory pump cannot deliver over 20. But this is better than 6. If I stomp the gas at a stop sign 50% of the time it will bog just a little bit. But sometimes it will backfire back through the tbi unit. I actually got my eyebrow hairs singed when I was in the engine bay and adjusting pressure. I manual hit the gas and "pow", fire, bog then back to idle

Fuel pump should be pumping 12-20 lbs. Set the regulator to 12 lbs. This is for a TBI, not a Vortec.