My setup is so basic so I can't understand why I'm having these issues.

MY2000
Comptech N1220 supercharged
Aiming for 350-375 WHP
Aeromotive 340 pump hardwired with relay to battery
Stock fuel lines
Stock rail (tapped for fuel pressure gauge)
ID1000 injectors
Stock FPR

I had an issue on the dyno a month ago where I was running out of fuel at the top end. Ben said he had my injectors maxed at the top and still the curve was pushing too lean around 8k RPM. He suggested replacing the pump. I put in a new pump, new stock FPR, and had my injectors cleaned/flow tested.

I also installed a fuel pressure gauge on the rail for troubleshooting. Now with all these new/fresh parts in, if I let the car idle with the vacuum line disconnected to the FPR, my base pressure is reading out as 64 PSI. Pretty sure base pressure should be 43 PSI using this method, right? A higher base pressure would explain why I was running out of fuel up top, because the pressure at that point would have been base pressure plus boost, which was 13 PSI, so I was running 77 PSI fuel pressure up top... at least that's what I've gathered from reading forum posts. So what could be causing my high base pressure issue?

 

The OEM FPR is capable of flowing the amount of fuel that the Aeromotive 340 delivers, right? I mean, several other people use the same fuel setup I'm using without issue...

 

77Psi fp. On 1000 cc injectors should have been capable of over 700 horsepower do you have a return system what year is your car

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I made 405whp with a drop in 255 and ID725s in 93 pump everything else stock on my novi1000. Now I'm aiming for around 600 on e85 with a Turbo and Evans said a walbro 416 and ID1300cc I can hit over 600whp. That's using stock rail,lines,and fpr.

So something isn't right

 

Its a MY00 AP1, stock feed/return lines.

 

That's what I thought... I just don't know what to look for! I will try to check the return lines to see if there is a kink/clog. There is a little filter basket on the outlet port from the fuel rail where the FPR mounts... could that be clogged and restricting flow through the outlet port? Maybe I'll remove that filter basket for now to see if it makes a difference.

 

I generally favor aftermarket FPR's at anything over a 255lph pump. Back in my SHO days, even a 255 was too much for the stock regulator.

 

I have a fuel pressure sensor for my EMS. With a 340lph pump, I observed a base pressure of ~58psi. I had to get a AEM FPR to get the base pressure down to 43psi. I doubt that the injectors are the bottle neck.

 

Thank you for this info. So you had a similar setup as me (340 pump, stock FPR, similar injectors) and experienced a high base pressure just like I am, and remedied it by replacing the FPR with a more free-flowing one. S**t, looks like I will be buying an AEM FPR.

I'm still going to check out my return line just to see if the rubber line is kinked anywhere or if there is any ding/damage to the metal hard line. But if everything looks right, then I guess I'll try out the AEM FPR.

Which flow insert did you end up using on your AEM FPR? I think it comes with two or three different inserts to achieve different flow through the FPR.

 

Do you think I this is from hardwiring the pump to the battery? I just used the harness in the stock hanger when I installed my pump. Hopefully there is enough voltage getting to it.