Fuel pump problem?

[arlo#1]

I am about to install my swirl pot I made and second fuel pump but am still a little worried. I drove my car to get the out of provance done the other day, and after i drive it a little the pump starts to wine and the wine just gets louder and louder I found a half tank was better then just a little bit of gas in the tank. But If I stay in the shop and dont move it will run forever and never make any noise from the pump. So I belive it is air getting into the fuel. That is why I built a surge tank and My only concern is wont the primay pump just do the same thing and start to wine un controlably? Or will it be different because it is not fighting the presure regulator and it will have basicly no presure? I have a pump I got for free, I mesured and it looks to flow 257 lph so I think it will be a 255 for a low presure pump I am not woried about much other than not fixing my problem.

[devastator]

I think the swirl pot will remedy your whining fuel pump problem. As long as the pump from the tank to the swirl pot can handle the volume of fuel that the engine needs, the swirl pot should take care of the air getting into the high pressure pump. The primary pump shouldn't whine as it is designed to flow at a lower pressure. Your primary pump is lower than the tank right?

[arlo#1]

I installed it and it did nothing I am wondering a bunch of things. first off to remember I can sit and tune the car in the shop for hours but as sone as it starts to be driven about 3 blocks later and it starts. It seems that it is whiping the fuel but I am not sure so I will pull off the little filter of the stock sending unit. I cant put fuel pump below the tank level and I cant fit one inside either. I am wondering if the new walbro 255 high presure punp is just garbage or what is happening. I can pinch off a return line and it makes it quieter. As well I am wondering if I should put a low presure restion in the swirl pot return?

[devastator]

Do you have a gauge hooked to the fuel rail somewhere where you can view it during driving? The few times my pump made noise, it was cavitating as it seems yours is doing, (I forgot to put gas in the tank). When it makes this noise, see if your fuel pressure drops too. You should feel a horsepower loss, if you lose fuel pressure, as well. If this is the case, I'd say your swirl pot is "sloshing" around because it's not full enough. Is the swirl pot higher than the EFI fuel pump?

[arlo#1]

For the swirl pot I designed it cant be higher than the pump the pump is flush with the top of it. But yes I belive the fuel pump is cavatating like crazy and once it starts it wont stop. I syphoned all the gas I could get out and it was just under 3 jery cans so about 2/3-3/4 of a tank was in it. I pulled the sending unit out and found the filter was loose on it and I yanked it off to try it. otherwise I am starting to think I need to hack the tunk floor for a fuel cell which I realy dont want to do! SHould I put a restrictor in the return from the swirl pot?

[devastator]

Do you have to have a return line from the swirl pot at all? Those small, electrical, low pressure, fuel pumps can "dead head" into a system with no problem. Is your low pressure pump mechanical?

[arlo#1]

Do you have to have a return line from the swirl pot at all? Those small, electrical, low pressure, fuel pumps can "dead head" into a system with no problem. Is your low pressure pump mechanical?

I had a efi pump kicking around and so I used it. I have a return line from the vey highest point of the swirl pot to the tank and that is what I am wondering if I should put a restrictor in. I am imagining a wirl pool in the tank to the pick up hapening and once the car drives around it starts to suck air into it! Would a fuel pump mounted lower then the fuel level stop this?

[arlo#1]

I have been playing this over and over in my mind I think a dead head pump as a primary might be the ticket with a presurized swirl pot. I am hoping matt cramer steps in now for the dodge dart has a simular tank to the road runner. I am just thinking if I can stop the whirl pool I visualize inside the tank it should work. So my therory is to slow the flow down when there is no need for it. Anyone with any ideas are welcome.

[devastator]

I should have been clearer. I was wondering if your EFI pump is lower that your swirlpot? I think a deadhead pump going to the swirlpot, then the EFI pump pick up at the bottom of the swirlpot, is the way to go. Where does your FPR send excess fuel to? In theory, a pressurized container, (swirlpot), should not have any air in it anyway. Maybe build a bleeder valve into the top of it in case you run out of fuel someday. Have you tried PM'ing Matt about his set-up? He usually answers so rapidly that it's like he has ESP or something.
BTW, just watched your youtube video. That's quite and intake, throttlebodies, and linkage! Cool!

[arlo#1]

I should have been clearer. I was wondering if your EFI pump is lower that your swirlpot? I think a deadhead pump going to the swirlpot, then the EFI pump pick up at the bottom of the swirlpot, is the way to go. Where does your FPR send excess fuel to? In theory, a pressurized container, (swirlpot), should not have any air in it anyway. Maybe build a bleeder valve into the top of it in case you run out of fuel someday. Have you tried PM'ing Matt about his set-up? He usually answers so rapidly that it's like he has ESP or something.
BTW, just watched your youtube video. That's quite and intake, throttlebodies, and linkage! Cool!

Hey thanks. And no the efi fuel pump is at the top of the swirl pot beside it and out side of it, it has a hose externaly that is plumbed from the very bottom of the swirl pot to the efi pump. I was thinking the dead head pump would work because it wont always have the wirlpool in the main tank because of the hi volume of fuel flow that I have now. I will try it soon with the filter off of the sending unit then buy the low presure dead head pump I found if I still need and plug off the return from the swirl pot if I need. Yeh My efi fuel presure regulator is plumbed back to the swirl pot. I will have to take pictures soon!

[devastator]

Sounds good. I was just thinking what provisions I have made to keep air out of my fuel system and there really aren't any. I sort of use my long fuel system to store enough extra fuel to eliminate the need for a swirl pot. I still have some fuel delivery problems associated with boost from the turbo, but the fuel pressure from the fuel pump never drops. Hmmm, something to think about during that commute to and from work everyday.

[arlo#1]

So I am still struggleing with this I have now a full tank of gas running to a holley lo presure dead head pump then to the top of a swirl pot which is now in my trunk to get it abouv the efi pump. Then from the very bottom of the swirl pot I run hose strait down to the efi pump then though all the fuel rails and then the pressure regulator then back to a tee in the top of the swirl pot and the other end of the tee goes back to the tank it self at first I made a very small jet to restrict the return to the tank but that didnt help so I took the restriction out and still nada. But I have made good progress it now can be driven around and have a little fun but when I open up the monster is when the efi pump starts to wine and I can tell by the data logs it starts to get very lean after a few pulls. But It seems I can go wide open first and second maybe third till it starts to have problems. SO i am now thinking about using a one way check valve going in the return line from the efi presure regulator. Or a restrictor in the top of the swirl pot which would be below the tee so the return fuel from the front seems to be airating the fuel. As I have determined it is only wide open that is when I have a problem. And at 6400 rpm I have about 90% duty cycle on 16 233cc injectors set at 80psi!

[devastator]

Can you remove the tee to the fuel tank all together? Just return the fuel form the fuel rail to the swirlpot? Does the pump in the tank have a "pressure relief", (like most stock fuel pumps), that will keep it from over pressurizing the swirlpot? If so, I'd just remove any return lines to the fuel tank.
That's an awfully high fuel pressure. I increased my fuel pressure beyond what the injector could close against properly and had similar problems, the difference being, I was running super rich, (although it sure felt lean). The datalog showed otherwise. Off hand, I'd say your problem is not in the fuel pumps or swirlpot, as much as the injectors being too small. That doesn't explain the pump noise though. Maybe try the removal of the tee from the swirlpot first?

[arlo#1]

I think I finaly got it I did some data logs and some city tuning from the pasengers seat and it went rich as soon as I swaped out the efi pump for the walbro 255 hi pressure pump to a random black one I found in a gold wing that the guy refuses to pick and or pay for here at work. The black one I pumped into a beaker to mesure the free flow for 7 sec and the calculations = 257 litre/hour so I belive it is another 255 but it may not be a high presure it didnt want to pump over 80psi (which is where I ended up with the presure to get it rich enough before and still had 93% duty cycles on the injectors as soon as I put this pump in it started to run rich every ware including the wide open throttle was at 10.2:1 a:f with the same maps and fuel presure so now I scaled the maps down and the presure down to 70 to try it some more. Looks like I might make the trip last minute anyway!

[arlo#1]

Can you remove the tee to the fuel tank all together? Just return the fuel form the fuel rail to the swirlpot? Does the pump in the tank have a "pressure relief", (like most stock fuel pumps), that will keep it from over pressurizing the swirlpot? If so, I'd just remove any return lines to the fuel tank.
That's an awfully high fuel pressure. I increased my fuel pressure beyond what the injector could close against properly and had similar problems, the difference being, I was running super rich, (although it sure felt lean). The datalog showed otherwise. Off hand, I'd say your problem is not in the fuel pumps or swirlpot, as much as the injectors being too small. That doesn't explain the pump noise though. Maybe try the removal of the tee from the swirlpot first?

You need a return from the swirl pot to the tank to push out the air other wise it will end up in the fuel system. I found the injectors had problems at 90 psi but not 80 so now I am at 70 psi and I might go a touch lower. But thanks for all the advice every one! One more day and I have a 2500mile round trip to a car show!