Fuel Pressure Still Dropping...
Mecham. Erneast..
People here are correct, having your FPR Fuel Pressure Reg hooked up to see Vac seeing 13Hg of Vac causes the Pressure to go down, but remember just a light touch at the Throttle the FP jumps as much as 5 to 13 psi as the Vac has gone from 13Hg to almost zero, then all the way to 13psi at WOT past 3000 rpms.. this 26 + - Fuel Pressure is hard to control, and might be hard on the pumps..
I would hook the hose line form the Fuel Pressure Reg to the Tubing of the Turbo, or anything before the Throttle Body blade. And I would set your Fuel Pressure to 58 or sotck for a ls1 motor.. Still have it so that when the Regulator sees Fuel Pressure it will go up. though Mighty Mouse is right, Having your pumps at 70 psi of pressure at these bigger lines -8an is though, and to just keep it at 58 to 60 psi might be the best..
Remember when you came over to the house, I mentioned that the Regulator needs to be hooked up before the TB Blade.. Also, Reason your running Rich in the Mid Range, is the tuning I setup for you is a liniar pull, going richer as you see the boost. Well the injectors are also seeing about 15% more fuel when the boost kicks in because the FP Reg is feeding it. I can tune this for you so it provides a consistant 11.7 A/F ratio for you, but as you know your running out of fuel for all the above reasons mentioned above and in the other posts. Having your pressure constant will be easier on the pumps and easier on the tune.
Take care.
Clint
People here are correct, having your FPR Fuel Pressure Reg hooked up to see Vac seeing 13Hg of Vac causes the Pressure to go down, but remember just a light touch at the Throttle the FP jumps as much as 5 to 13 psi as the Vac has gone from 13Hg to almost zero, then all the way to 13psi at WOT past 3000 rpms.. this 26 + - Fuel Pressure is hard to control, and might be hard on the pumps..
I would hook the hose line form the Fuel Pressure Reg to the Tubing of the Turbo, or anything before the Throttle Body blade. And I would set your Fuel Pressure to 58 or sotck for a ls1 motor.. Still have it so that when the Regulator sees Fuel Pressure it will go up. though Mighty Mouse is right, Having your pumps at 70 psi of pressure at these bigger lines -8an is though, and to just keep it at 58 to 60 psi might be the best..
Remember when you came over to the house, I mentioned that the Regulator needs to be hooked up before the TB Blade.. Also, Reason your running Rich in the Mid Range, is the tuning I setup for you is a liniar pull, going richer as you see the boost. Well the injectors are also seeing about 15% more fuel when the boost kicks in because the FP Reg is feeding it. I can tune this for you so it provides a consistant 11.7 A/F ratio for you, but as you know your running out of fuel for all the above reasons mentioned above and in the other posts. Having your pressure constant will be easier on the pumps and easier on the tune.
Take care.
Clint
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Originally Posted by HUGGER ORANGE SS
I would hook the hose line form the Fuel Pressure Reg to the Tubing of the Turbo, or anything before the Throttle Body blade. And I would set your Fuel Pressure to 58 or sotck for a ls1 motor
???????????
Originally Posted by HUGGER ORANGE SS
Mecham. Erneast..
People here are correct, having your FPR Fuel Pressure Reg hooked up to see Vac seeing 13Hg of Vac causes the Pressure to go down, but remember just a light touch at the Throttle the FP jumps as much as 5 to 13 psi as the Vac has gone from 13Hg to almost zero, then all the way to 13psi at WOT past 3000 rpms.. this 26 + - Fuel Pressure is hard to control, and might be hard on the pumps..
I would hook the hose line form the Fuel Pressure Reg to the Tubing of the Turbo, or anything before the Throttle Body blade. And I would set your Fuel Pressure to 58 or sotck for a ls1 motor.. Still have it so that when the Regulator sees Fuel Pressure it will go up. though Mighty Mouse is right, Having your pumps at 70 psi of pressure at these bigger lines -8an is though, and to just keep it at 58 to 60 psi might be the best..
Remember when you came over to the house, I mentioned that the Regulator needs to be hooked up before the TB Blade.. Also, Reason your running Rich in the Mid Range, is the tuning I setup for you is a liniar pull, going richer as you see the boost. Well the injectors are also seeing about 15% more fuel when the boost kicks in because the FP Reg is feeding it. I can tune this for you so it provides a consistant 11.7 A/F ratio for you, but as you know your running out of fuel for all the above reasons mentioned above and in the other posts. Having your pressure constant will be easier on the pumps and easier on the tune.
Take care.
Clint
People here are correct, having your FPR Fuel Pressure Reg hooked up to see Vac seeing 13Hg of Vac causes the Pressure to go down, but remember just a light touch at the Throttle the FP jumps as much as 5 to 13 psi as the Vac has gone from 13Hg to almost zero, then all the way to 13psi at WOT past 3000 rpms.. this 26 + - Fuel Pressure is hard to control, and might be hard on the pumps..
I would hook the hose line form the Fuel Pressure Reg to the Tubing of the Turbo, or anything before the Throttle Body blade. And I would set your Fuel Pressure to 58 or sotck for a ls1 motor.. Still have it so that when the Regulator sees Fuel Pressure it will go up. though Mighty Mouse is right, Having your pumps at 70 psi of pressure at these bigger lines -8an is though, and to just keep it at 58 to 60 psi might be the best..
Remember when you came over to the house, I mentioned that the Regulator needs to be hooked up before the TB Blade.. Also, Reason your running Rich in the Mid Range, is the tuning I setup for you is a liniar pull, going richer as you see the boost. Well the injectors are also seeing about 15% more fuel when the boost kicks in because the FP Reg is feeding it. I can tune this for you so it provides a consistant 11.7 A/F ratio for you, but as you know your running out of fuel for all the above reasons mentioned above and in the other posts. Having your pressure constant will be easier on the pumps and easier on the tune.
Take care.
Clint
1.The FP does not drop 13psi, due to the regulator seeing 13" of vac.
2. The injectors are not seeing 15% more fuel, as the boost is not only on the regulator side of the flow, it's also seen at the nozzle end. They cancel each other out, and the fuel volume is then controlled by "delta P", AKA, "net pressure".
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Originally Posted by MECHAM
Clint...so this is how i should hook things up then?
will i need to re-scale the injectors clint?
Mecham...
the Diagram looks good!.. Does the WasteGate need to see Boost and Vac? I'm not sure.. Ya hook the F P R up to the turbo tubing so it sees only boost, ya boost baby boost..
1:1 ratio is fine, ad the 58psi should work fine. The Ltrims will be slightly off, but not a big deal with the added Fuel Pressure.
I run both pumps at the same time, have been for over a year with no issues, so I would not worry too much about heat from the fact your running 2 pumps..
talk to you later.
Clint
the Diagram looks good!.. Does the WasteGate need to see Boost and Vac? I'm not sure.. Ya hook the F P R up to the turbo tubing so it sees only boost, ya boost baby boost..
1:1 ratio is fine, ad the 58psi should work fine. The Ltrims will be slightly off, but not a big deal with the added Fuel Pressure.
I run both pumps at the same time, have been for over a year with no issues, so I would not worry too much about heat from the fact your running 2 pumps..
talk to you later.
Clint
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update Apr 29
verified both pumps are working. i would assume that if they turn on that they are working. no leaks...verified.
hooked up the system like the above pic, so the fpr only sees boost and rises 1:1.
static fpr 52-53psi
fuel pressure is still dropping during WOT runs...for 7psi no...13psi yes.
any1 running 3 pumps? cheap route to add another pump gss340...
or
should i drop the static pressure down to to 43psi like MM suggest and try that?
verified both pumps are working. i would assume that if they turn on that they are working. no leaks...verified.
hooked up the system like the above pic, so the fpr only sees boost and rises 1:1.
static fpr 52-53psi
fuel pressure is still dropping during WOT runs...for 7psi no...13psi yes.
any1 running 3 pumps? cheap route to add another pump gss340...
or
should i drop the static pressure down to to 43psi like MM suggest and try that?
Last edited by MECHAM; Apr 29, 2006 at 05:19 PM.
Originally Posted by MECHAM
update Apr 29
verified both pumps are working. i would assume that if they turn on that they are working. no leaks...verified.
hooked up the system like the above pic, so the fpr only sees boost and rises 1:1.
static fpr 52-53psi
fuel pressure is still dropping during WOT runs...for 7psi no...13psi yes.
any1 running 3 pumps? cheap route to add another pump gss340...
or
should i drop the static pressure down to to 43psi like MM suggest and try that?
verified both pumps are working. i would assume that if they turn on that they are working. no leaks...verified.
hooked up the system like the above pic, so the fpr only sees boost and rises 1:1.
static fpr 52-53psi
fuel pressure is still dropping during WOT runs...for 7psi no...13psi yes.
any1 running 3 pumps? cheap route to add another pump gss340...
or
should i drop the static pressure down to to 43psi like MM suggest and try that?
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Verdad Gallardo You Could Try with 43 psi like MM said..
Or I would Up the voltage to the Pumps at WOT, and here's the perfect thing to do it with..
https://www.casperselectronics.com/M...&Category_Code
My buddy is running this and it works well for him he's 550RWHP with 1 single pump.
what does your FP go to at WOT 13psi of boost?
Or I would Up the voltage to the Pumps at WOT, and here's the perfect thing to do it with..
https://www.casperselectronics.com/M...&Category_Code
My buddy is running this and it works well for him he's 550RWHP with 1 single pump.
what does your FP go to at WOT 13psi of boost?
if you dont manifold reference your regulator then wtf does your injector flowrate table look like?
easy to have a nice constant value and give it vaccum and boost. thats where they are placed for all oem (or are not referenced at all)
having it boost only certainly would have no affect on fp stability at higher pressures.
either you have a kink or break in the line inside or outside the tank, or your voltage at wot is not holding 13v.
every psi you turn the regulator down is one more psi it wont drop on you at wot.. yea maybe you should try what i said
easy to have a nice constant value and give it vaccum and boost. thats where they are placed for all oem (or are not referenced at all)
having it boost only certainly would have no affect on fp stability at higher pressures.
either you have a kink or break in the line inside or outside the tank, or your voltage at wot is not holding 13v.
every psi you turn the regulator down is one more psi it wont drop on you at wot.. yea maybe you should try what i said
Originally Posted by MECHAM
update Apr 29
verified both pumps are working. i would assume that if they turn on that they are working. no leaks...verified.
hooked up the system like the above pic, so the fpr only sees boost and rises 1:1.
static fpr 52-53psi
fuel pressure is still dropping during WOT runs...for 7psi no...13psi yes.
any1 running 3 pumps? cheap route to add another pump gss340...
or
should i drop the static pressure down to to 43psi like MM suggest and try that?
verified both pumps are working. i would assume that if they turn on that they are working. no leaks...verified.
hooked up the system like the above pic, so the fpr only sees boost and rises 1:1.
static fpr 52-53psi
fuel pressure is still dropping during WOT runs...for 7psi no...13psi yes.
any1 running 3 pumps? cheap route to add another pump gss340...
or
should i drop the static pressure down to to 43psi like MM suggest and try that?
I'm trying two A1000's.
Erneast..
I would do what MM said.. Now that I think about it the 255l per hour flow rate is at 45psi I believe. So it makes since you can max the Flow of your pumps by doing 2 things.. Lower the PSI to what MM said, and also upping the voltage to the pumps, from 12-13 to 16volts if you can..
Tuning your car for 43psi fuel pressure is not a problem..
Clint
I would do what MM said.. Now that I think about it the 255l per hour flow rate is at 45psi I believe. So it makes since you can max the Flow of your pumps by doing 2 things.. Lower the PSI to what MM said, and also upping the voltage to the pumps, from 12-13 to 16volts if you can..
Tuning your car for 43psi fuel pressure is not a problem..
Clint
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thx clint...
was gonna order that casper do-dad u posted earlier...did a search on here and noyzee is selling a brand new one .. so i got it from him instead (saved about $40.
gonna lower the FP to 43psi too....increase the injectors...and pray my fp stays. if not....3 pumps here i come
was gonna order that casper do-dad u posted earlier...did a search on here and noyzee is selling a brand new one .. so i got it from him instead (saved about $40.
gonna lower the FP to 43psi too....increase the injectors...and pray my fp stays. if not....3 pumps here i come
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update...
2...is better than 1....3 is better than 2.
yep...3 intank walbros...holy scheeit it was a tight fit.
wasnt too bad EXCEPT the fuel pump relay went bad...at the same time I was adding the 3rd pump...took me about 6hrs to figure that one out...i cant tell you how many times i rewired the pumps...put it in..pulled it out...in..out...fuses..etc..etc 
anyways..minus that detour
prelim 12psi tests show 0 drop in pressure.
its running really rich now...did that and the 2bar new tune so everything is out of whack.....again.
im getting lots of knock too...hope this is because of the richness? wideband : richness
2...is better than 1....3 is better than 2.
yep...3 intank walbros...holy scheeit it was a tight fit.
wasnt too bad EXCEPT the fuel pump relay went bad...at the same time I was adding the 3rd pump...took me about 6hrs to figure that one out...i cant tell you how many times i rewired the pumps...put it in..pulled it out...in..out...fuses..etc..etc anyways..minus that detour
prelim 12psi tests show 0 drop in pressure.
its running really rich now...did that and the 2bar new tune so everything is out of whack.....again.
im getting lots of knock too...hope this is because of the richness?
wideband : richness Mecham...
I guess 3 Walbros are better Arnt they
I suppose at that point people would have gone with that Aeromotive 1000 hp pump, but I don't think that flows 765L per hour of fuel.. It is amazing your car needs 201Gallons of fuel per hour flow but I guess it does. Impressive..
Not supprised your tune is off now..
we shall take care of that.
Clint
I guess 3 Walbros are better Arnt they
I suppose at that point people would have gone with that Aeromotive 1000 hp pump, but I don't think that flows 765L per hour of fuel.. It is amazing your car needs 201Gallons of fuel per hour flow but I guess it does. Impressive..
Not supprised your tune is off now..
we shall take care of that.
Clint
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well...nix the 3 pumps. with the tank low, the heat of the pumps was too much and one of the pumps burnt out. and while undoing everything i broke off one of the inlets for one of the other pumps. so now my plan is... 2 pumps .. 43 psi .. and i hooked up the casper volt booster. gotta get another pump 2morrow.
Why dont u go with a one 255 intake and a 420 Bosch mounted outside the tank with a feed line going in then connect the feed lines from both pumps with a Y block outside the tank. Thats what we are trying to do now. The nice thing about the Bosch is that it will hold high pressure better than another 255 intank.
dont run any more than 1 pump ALL the time.
also i promise if you have two GOOD 255's in there and no restrictions on the pressure side between them and the rails (and a good regulator) you will not have pressure problems.
also i promise if you have two GOOD 255's in there and no restrictions on the pressure side between them and the rails (and a good regulator) you will not have pressure problems.
Earnest..
I'm sorry, but I must stress again.. Your 3 Walbro Pump idea was perfect, but don't know why you had all 3 on at the same time.. Like I said you need to have a RPM or WOT switch to activate the #3 pump. Seems like having 2 on is okay, but 3 will create Heat!! Also I hope you mounted these in your tank with a little space between each pump. Having all 3 touch each other metal on metal will cause a problem.. place some rubber between each. I did like MM did, I placed cut 3/8" rubber hose between each pump to cusion between and put a hose clamp on them.
Clint
I'm sorry, but I must stress again.. Your 3 Walbro Pump idea was perfect, but don't know why you had all 3 on at the same time.. Like I said you need to have a RPM or WOT switch to activate the #3 pump. Seems like having 2 on is okay, but 3 will create Heat!! Also I hope you mounted these in your tank with a little space between each pump. Having all 3 touch each other metal on metal will cause a problem.. place some rubber between each. I did like MM did, I placed cut 3/8" rubber hose between each pump to cusion between and put a hose clamp on them.
Clint