Do Adj Fuel Pressure Reg increase FP under boost?

GTLee · 10-15-2001, 11:57 AM

Hey guys,

I have a BBK adj FPR installed in my 5.0. I also have a BD-11A blower running at 11psi, 190l/hr fuel pump, 24lb injectors (incase it's not in the signature).

I know that the FPR will lower the FP under vacuum but does it raise FP under boost (ala an FMU)?

Also how bad for my fuel system (pump, injecters, rails, etc) will it be to run at 55-60psi (vacuum off) all the time and run w/o the FMU?

Thanks guys.

------------------
-Engine: K&N, 75mm MAF with 24# Injectors, 65mm TB, Trick Flow Street Intake, 1.7 Roller Rockers, Adj FPR (set at 35psi), 190lph FP
-Exhaust: MAC 1 5/8" Headers, Catco 2.25" h-pipe, MagnaFlow mufflers
-Drivetrain: World Class T-5Z, Aluminum Driveshaft, 3.55 gears
-Suspension: Subframe Connectors and K-Brace, KYB Shocks and Struts, BBK Upper and Lower Control Arms
-Dyno: 208.7rwhp, 262.9ft/lb torque

LOWKEY · 10-15-2001, 04:25 PM

Yes most afpr do increase fp under boost. At least my paxton one does. My base pressure is around 40 and I see almost 50 under full boost. Its almost a 1 to 1 ratio.

As for running 55-60lbs vacuum off, don't do it. I mean it will run really bad down low and you will get really bad gas mileage.

Do you have any idea how much pressure you are running under boost with the fmu? What disk do you have? I would highly recommend larger injectors, say 42's and a 80mm pro-m, FMU's are unrealiable and slow. You also need a larger fuel pump, the walbro 255lph for forced induction would work perfect.

Just trying to help, good luck...
Brad

------------------
89'notch

331ci Scat Stroker, Stage II Holley heads, ported Holley Systemax Intake, 70mm Holley TB, 50lb Holley Fuel Injectors, 80mm Pro-m MAF, AFM B-3 cam, Vortech S-trim Supercharger, AFM Powerpipe, EEC-Tuner, TKO, Koni, Eibach, HPM, etc...

Beaten Daily..

http://lowkey.stangnet.com

10-15-2001, 11:57 AM	#1
GTLee Registered Member Join Date: Mar 1999 Location: Yonkers, NY Posts: 19	Do Adj Fuel Pressure Reg increase FP under boost? Hey guys, I have a BBK adj FPR installed in my 5.0. I also have a BD-11A blower running at 11psi, 190l/hr fuel pump, 24lb injectors (incase it's not in the signature). I know that the FPR will lower the FP under vacuum but does it raise FP under boost (ala an FMU)? Also how bad for my fuel system (pump, injecters, rails, etc) will it be to run at 55-60psi (vacuum off) all the time and run w/o the FMU? Thanks guys. ------------------ -Engine: K&N, 75mm MAF with 24# Injectors, 65mm TB, Trick Flow Street Intake, 1.7 Roller Rockers, Adj FPR (set at 35psi), 190lph FP -Exhaust: MAC 1 5/8" Headers, Catco 2.25" h-pipe, MagnaFlow mufflers -Drivetrain: World Class T-5Z, Aluminum Driveshaft, 3.55 gears -Suspension: Subframe Connectors and K-Brace, KYB Shocks and Struts, BBK Upper and Lower Control Arms -Dyno: 208.7rwhp, 262.9ft/lb torque

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10-15-2001, 04:25 PM	#2
LOWKEY Registered Member Join Date: Jan 2000 Location: greenvile, NC Posts: 161	Yes most afpr do increase fp under boost. At least my paxton one does. My base pressure is around 40 and I see almost 50 under full boost. Its almost a 1 to 1 ratio. As for running 55-60lbs vacuum off, don't do it. I mean it will run really bad down low and you will get really bad gas mileage. Do you have any idea how much pressure you are running under boost with the fmu? What disk do you have? I would highly recommend larger injectors, say 42's and a 80mm pro-m, FMU's are unrealiable and slow. You also need a larger fuel pump, the walbro 255lph for forced induction would work perfect. Just trying to help, good luck... Brad ------------------ 89'notch 331ci Scat Stroker, Stage II Holley heads, ported Holley Systemax Intake, 70mm Holley TB, 50lb Holley Fuel Injectors, 80mm Pro-m MAF, AFM B-3 cam, Vortech S-trim Supercharger, AFM Powerpipe, EEC-Tuner, TKO, Koni, Eibach, HPM, etc... Beaten Daily.. http://lowkey.stangnet.com