Running out of fuel
#1
Running out of fuel
I'm too tired to research this fully. Please help.
Just got out of a shop and we had to call it quits at 355hp. Due to fuel (or lack of).
1050x, DW300 pump, e85, all braided 6-an lines, return setup with fuel lab pressure regulator at 45 psi. Running a dual rail from FM.
fuel goes from DW300 - 6-an teflon lines - Fuel Labs giant filter - GM sensor - FM rail - 1050x - return to Fuel Labs regulator - return to tank (6-an again).
Red graph is at 22psi. You can see my fuel pressure ***** the bed and heads south. Then at the very top end it is enough of a drop to see the AFR start rising. Didn't even try to get above 6000 rpm in this case.
Blue is at 18psi. 320hp and looking fine.
Tuner recommends a surge tank or larger pump.
Just got out of a shop and we had to call it quits at 355hp. Due to fuel (or lack of).
1050x, DW300 pump, e85, all braided 6-an lines, return setup with fuel lab pressure regulator at 45 psi. Running a dual rail from FM.
fuel goes from DW300 - 6-an teflon lines - Fuel Labs giant filter - GM sensor - FM rail - 1050x - return to Fuel Labs regulator - return to tank (6-an again).
Red graph is at 22psi. You can see my fuel pressure ***** the bed and heads south. Then at the very top end it is enough of a drop to see the AFR start rising. Didn't even try to get above 6000 rpm in this case.
Blue is at 18psi. 320hp and looking fine.
Tuner recommends a surge tank or larger pump.
#7
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I'm too tired to research this fully. Please help.
Just got out of a shop and we had to call it quits at 355hp. Due to fuel (or lack of).
1050x, DW300 pump, e85, all braided 6-an lines, return setup with fuel lab pressure regulator at 45 psi. Running a dual rail from FM.
Just got out of a shop and we had to call it quits at 355hp. Due to fuel (or lack of).
1050x, DW300 pump, e85, all braided 6-an lines, return setup with fuel lab pressure regulator at 45 psi. Running a dual rail from FM.
If you want to keep the DW300 and maximize its capabilities, I would probably do 55psi of base pressure and keep peak boost under 25psi. That will give you 1145cc/min of capacity from the pump (assuming ~80psi max outlet pressure), and ID1050s at 55psi DFP are good for exactly that. At 55psi, you'll have enough fuel to get to the 400whp mark safely, but if you need more, you'll either need more fuel pump (Walbro 400-E85) or bigger injectors.
#8
alternator is strong.
Sav has it. I just looked and I'm at 69% duty cycle at 18psi (320hp) and 83% at 22psi (355hp).
I'll put the fuel pressure up at 55psi and re-log some runs.
I want a solid 350hp with plenty of headroom (looking for the infamous tranny wrecking 400). I'll head back to the dyno once that is accomplished.
Thanks Sav!
Sav has it. I just looked and I'm at 69% duty cycle at 18psi (320hp) and 83% at 22psi (355hp).
I'll put the fuel pressure up at 55psi and re-log some runs.
I want a solid 350hp with plenty of headroom (looking for the infamous tranny wrecking 400). I'll head back to the dyno once that is accomplished.
Thanks Sav!
#11
Former Vendor
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On second look, I missed that fuel pressure log. Even with 45psi of base pressure, you should be maintaining 45psi to redline, not dropping to 32psi. There's ALSO something up with your pump or filter.
Keep in mind that 400whp corrected at 5000ft of elevation takes a lot less fuel (18-20%) than making 400whp corrected at sea level.
Keep in mind that 400whp corrected at 5000ft of elevation takes a lot less fuel (18-20%) than making 400whp corrected at sea level.
#13
I just had a realization. I replaced the OEM pump with the DW300 and never changed the fittings on the sub-plate thing. So the 6AN has an ID of like 0.3-0.34". BUT, the little swept right angle SAE quick disconnect pipe that dives down into the fuel tank is smaller. I don't know by how much.
Do I have to weld on a replacement fuel fitting?
Do I have to weld on a replacement fuel fitting?
#19
Tweaking Enginerd
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I would seriously consider moving the sensor to the return if it is not already there. I have personaally seen one of these get plugged by a foriegn object. On that install, the sensor was on the return, so the result was an extreme rich (safe) condition. If the sensor had been on the source line, it most likely would have been catastrophic.
#20
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Have you ever looked down the barrel of a GM flex fuel sensor? It's nearly wide open. If it gets plugged with something, you're either running absolutely no form of fuel filtration whatsoever, or your injectors and FPR will shortly be so fucked that it won't matter anyway.
If you aren't making a thousand horsepower, there is absolutely no reason to run the sensor in the return line. Running it in the feed line immediately before the injectors gives the most accurate data possible to the ECU for ethanol trims, especially during transition between E85 and gasoline.
If you aren't making a thousand horsepower, there is absolutely no reason to run the sensor in the return line. Running it in the feed line immediately before the injectors gives the most accurate data possible to the ECU for ethanol trims, especially during transition between E85 and gasoline.