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Discussion Starter #1
I cant find the blasted search button anymore!!!!

I have a FPR, stock injectors, walbro 255, Apexi filter, greddy profecBII, mandrel bent 2.5" 3.0· coming up, I am running 0.60Bar stock was 0.45b and plan to run 1.0 Bar your 14.5psi,I need to know what should I put my fuel pressure to, I have it at 35 thats what the manual for the fpr said, but my car is gobbling up fuel now :p I changed the O2 sensor yesterday and havent checked on fuel consumption but I think it doesnt run like it should be
 

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Discussion Starter #4
Jesus now I feel stupid, thank you about that!!!!

Any ideas of how should I increment pressure with higher boost? or should I leave it stock pressure
 

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I have mine set at 36psi when the Supra is at idle with vacuum line in. Currently running PTE 550cc injectors, Walbro 255lph fuel pump, Lexus AFM (screw is backed out about 2/3-3/4. Also have a wideband sensor. Even on the current setting, it runs really rich once I go into boost. At 40psi of fuel pressure, the car won't even idle with the Lex AFM screw all the way out. J-tube bend has already been eliminated too.
 

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man everyone has way higher psi then the tsrm. what is a good pressure to start at anyway? tsrm says 23-30 with vac line in. is that too lean with the same mods as above? im guessing your wideband is reading correct so that was probably your best setting correct?
 

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Discussion Starter #7
Well mine was set at what the Aeromotive instructions said...

I lowered mine to 32psi and the car pulls much stronger now, I was gobbling up fuel and not running like it should, I need to get a wideband ffs

Thanks to all :)
 

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Wide band is the way to go. Engine vital signs are the best way to determine your current state. If you have made changes to stock engineering, you need to monitor your modifications.
Having a stock turbo, you don't have to increase FP to keep up with boost increase. That's the job of the FPR. It functions on a 1:1 ratio, meaning, it will increase the FP 1PSI for every PSI of boost you feed into your engine.
If you have supplemented with bigger injectors, chances are you won't need to "up" your base FP. You've just supplemented your fuel with the injectors so why up your FP too?
Keep your FP at stock setting till the WB tells you you need more fuel.
That will usually happen with a bigger turbo.
If you have a fuel computer, IE an SAFR or an SAFC, make your adjustments with the AFPR to get it close, then fine tune with the fuel computer. If you make major adjustments with the fuel computer, you will alter your timing.

Will
 

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Discussion Starter #9
AH!!! so the FPR increments preassure with boost, I was a bit worried becouse when I accelerated the car pulling the throttle linkage , i was seeing the pressure drop :)
I will lower it to stock then, Im getting bangs from my exhaust when I shift at half throttle and the Bov sounds, thats because its still running pig rich?
 

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AH!!! so the FPR increments preassure with boost, I was a bit worried becouse when I accelerated the car pulling the throttle linkage , i was seeing the pressure drop :)
I will lower it to stock then, Im getting bangs from my exhaust when I shift at half throttle and the Bov sounds, thats because its still running pig rich?
Running rich may make it backfire but I never had a backfiring problem when I ran rich. You might have problems elsewhere. The reason I think this is because you said your pressure actually went up when you put the vac line on your FPR. The pressure should go down when you attach the vac line. Stock specs say 33-40PSI with the hose off and 23-30 with it on. I don't ever remember my pressure dropping when I revved my engine either. I'd get my fuel system checked out professionally and or get a WB so you know exactly what's going on with your A/F.
You surely don't want to chance blowing your engine on a guess.
 

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with the Vac line off you should be at 38-42psi of fuel pressure if you are running anything other than stock boost. this is where the walbro pump is in its efficiency range.
 

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with the Vac line off you should be at 38-42psi of fuel pressure if you are running anything other than stock boost. this is where the walbro pump is in its efficiency range.
Why add more FP when the FPR automatically does it for you when you raise the boost? The Walbro can produce more than 80PSI of unleashed pressure. It will be efficient at any FP you set. The efficiency needs to be in the cylinders. As long as he has a stock turbo, he'll be fine with stock FP if his whole fuel system is intact. With stock turbo and injectors, it will still appreciate stock FP.
Raise boost, the AFPR will do the rest. He won't get it to his target 14.7 boost without more work but till then he can raise up to fuel cut.
 
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