I want to convert my 454 TBI to an external regulator and want to locate the regulator in the RETURN line. Can someone please tell me which regulator and which fuel pump to use? I'd like manufacturer's names and part numbers if possible. I've read on this board that a late model truck fuel pump is used. What is the application? (year, engine size, OR part number) I will be gutting the TBI internal regulator. I will be using this setup on my ZZ4/T56 1992 S-10.

Thanks,
Mike

 

first off, you do not need to "gut" the stock regulator

secondly, any external regulator will do, be it a mallory, a barry grant, or in my case, a NOS regulator. Id just look for whichever one was priced lowest. Youll be fine as long as it can adjust in the range you plan on running your tbi at, in my case my regulator came with two springs one for low pressure (0-15) and one for high which is 15-50, i use the high pressure spring and run a little under 20 psi

Im the one who is using the late model truck pump. I cannot recall the part number off hand I believe its P31 in blackstone but im not certain. Ask the parts counterman for the fuel pump book it comes with a chart of pump flow and pressure. My pump is rated at 42 GPH at 36 psi. I believe the apps were for later model vortec pickup trucks and some cadillacs.

BTW that sounds like a KILLER combo! be sure to get the chip side right and have enough injector for it

 

OK......what size injectors should I use? My 454 TB has 80# injectors. Will these be OK? Or should I drop down to 65# and increase fuel pressure. How much pressure should I run? I'm looking for a ballpark figure for initial start-up. The ZZ4 is rated 355 HP by GM. "My" ZZ4 may be closer to 365 HP because I have bumped compression to 10.4 and have 1.6 rockers on the intake valves.

Thanks,
Mike

 

Two 80# units at stock pressure will be enough fuel for approx 320hp. You will probably have to raise the pressure to prevent a lean condition at WOT.

In other words, forget the 65# units. They would require even more pressure to deliver the needed fuel and place unnessary load on the fuel pump.

Any rich condition at part throttle and idle is not an injector problem but a calibration problem in the prom.