Returnless Fuel System
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Vehicle: Elantra HD / 2007
I tried to searc about it but become more confused 
1. Does all Tiburon (MAF and MAP based) have return fuel system?
2. What system is better? (any hp gains)?
3. Why to change fuel system to returnless?
4. Will fuel consumption be bigger in returnles system?
1. Does all Tiburon (MAF and MAP based) have return fuel system?
2. What system is better? (any hp gains)?
3. Why to change fuel system to returnless?
4. Will fuel consumption be bigger in returnles system?
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Joined: Nov 2003
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From: Rancho Palos Verdes, CA
In a "normal" fuel system. The fuel pump is constantly running sending as much fuel as it possibly can at the pressure set by the fuel pressure regulator.
The "normal" Fuel Pressure regulator maintains fuel pressure of about 43psi (little less at times of high vacuum, but about 43psi at atsmopheric pressure(wide open throttle)). The fuel pressure regulator allows enough fuel to "bypass" the regulator to keep the pressure at the proper level. The bypassed fuel returns to the fuel tank via a seperate, yet paralell line next to the primary feed line.
The advantages of a "return" style fuel system is that it allows you to run basically any size fuel pump (as long as it is big enough to meet engine demand). You can run a 150 LPH pump or a 300 LPH pump. The Fuel Pressure regulator does it's job bypassing the extra fuel. It's also very simple to setup, and fairly simple to modify.
The disadvantages of a "return" style fuel system is that it heats the fuel. Anytime you pressurize something, you heat it. So the return system of constantly recycling/pressurinzing more fuel than is needed heats the gas. Running the gas through the hot engine compartment time and time again also heats the fuel.
"Returnless" systems are very different. The fuel pump has it's own pressure sensor built into the pump. It speeds up and slows down as the engine's fuel needs vary. There is only ONE fuel line supplying the motor, and no return line. There is a fuel pressure dampner on the end of the fuel rail in place of a fuel pressure regulator. It's job is to absorb fuel presure waves and prevent wild flucuations in fuel pressure as the pump varies it's rate of flow attempting to match engine demand. The Fuel pump is controled via it's own built in fuel pressure regulator and via the ECU. When you apply the throttle, the ECU sends the signal to the fuel pump to increase flow, in time with throttle position. The fuel pressure regulator built into the pump can "over-ride" the ECU signal to prevent fuel pressure spikes or dips.
The Advantage of a "returnless" fuel system is that it is more compact, lighter and more efficent (thermally and electrically)
The disadvantage is that returnless systems are much, much harder to modify. Because the fuel pressure is set within the pump itself, and controled via the ecu. Modifications to both are required to increase fuel pressure/flow.
The switch to returnless fuel systems has been made for emissions reasons, not for fuel economy reasons. Heating the fuel causes the lighter hydrocarbons to evaporate out. The returnless system does not put as much heat into the fuel, so not as much evaporation occurs.
Switching to a returnless system is not an option. You would need to replace the pump, the hosing, the ECU and the fuel rail. It's just not feasable.
Beta1's are all "return" based systems. Some Beta2's are "returnless" and some are 'return' systems. In general, the Beta2's in the USA are returnless.
The "normal" Fuel Pressure regulator maintains fuel pressure of about 43psi (little less at times of high vacuum, but about 43psi at atsmopheric pressure(wide open throttle)). The fuel pressure regulator allows enough fuel to "bypass" the regulator to keep the pressure at the proper level. The bypassed fuel returns to the fuel tank via a seperate, yet paralell line next to the primary feed line.
The advantages of a "return" style fuel system is that it allows you to run basically any size fuel pump (as long as it is big enough to meet engine demand). You can run a 150 LPH pump or a 300 LPH pump. The Fuel Pressure regulator does it's job bypassing the extra fuel. It's also very simple to setup, and fairly simple to modify.
The disadvantages of a "return" style fuel system is that it heats the fuel. Anytime you pressurize something, you heat it. So the return system of constantly recycling/pressurinzing more fuel than is needed heats the gas. Running the gas through the hot engine compartment time and time again also heats the fuel.
"Returnless" systems are very different. The fuel pump has it's own pressure sensor built into the pump. It speeds up and slows down as the engine's fuel needs vary. There is only ONE fuel line supplying the motor, and no return line. There is a fuel pressure dampner on the end of the fuel rail in place of a fuel pressure regulator. It's job is to absorb fuel presure waves and prevent wild flucuations in fuel pressure as the pump varies it's rate of flow attempting to match engine demand. The Fuel pump is controled via it's own built in fuel pressure regulator and via the ECU. When you apply the throttle, the ECU sends the signal to the fuel pump to increase flow, in time with throttle position. The fuel pressure regulator built into the pump can "over-ride" the ECU signal to prevent fuel pressure spikes or dips.
The Advantage of a "returnless" fuel system is that it is more compact, lighter and more efficent (thermally and electrically)
The disadvantage is that returnless systems are much, much harder to modify. Because the fuel pressure is set within the pump itself, and controled via the ecu. Modifications to both are required to increase fuel pressure/flow.
The switch to returnless fuel systems has been made for emissions reasons, not for fuel economy reasons. Heating the fuel causes the lighter hydrocarbons to evaporate out. The returnless system does not put as much heat into the fuel, so not as much evaporation occurs.
Switching to a returnless system is not an option. You would need to replace the pump, the hosing, the ECU and the fuel rail. It's just not feasable.
Beta1's are all "return" based systems. Some Beta2's are "returnless" and some are 'return' systems. In general, the Beta2's in the USA are returnless.
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Joined: Dec 2006
Posts: 24
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Vehicle: hyundai accent 1996
<div class='quotetop'>QUOTE (Random @ May 22 2005, 08:57 PM) <{POST_SNAPBACK}></div><div class='quotemain'>In a "normal" fuel system. The fuel pump is constantly running sending as much fuel as it possibly can at the pressure set by the fuel pressure regulator.
The "normal" Fuel Pressure regulator maintains fuel pressure of about 43psi (little less at times of high vacuum, but about 43psi at atsmopheric pressure(wide open throttle)). The fuel pressure regulator allows enough fuel to "bypass" the regulator to keep the pressure at the proper level. The bypassed fuel returns to the fuel tank via a seperate, yet paralell line next to the primary feed line.
The advantages of a "return" style fuel system is that it allows you to run basically any size fuel pump (as long as it is big enough to meet engine demand). You can run a 150 LPH pump or a 300 LPH pump. The Fuel Pressure regulator does it's job bypassing the extra fuel. It's also very simple to setup, and fairly simple to modify.
The disadvantages of a "return" style fuel system is that it heats the fuel. Anytime you pressurize something, you heat it. So the return system of constantly recycling/pressurinzing more fuel than is needed heats the gas. Running the gas through the hot engine compartment time and time again also heats the fuel.
"Returnless" systems are very different. The fuel pump has it's own pressure sensor built into the pump. It speeds up and slows down as the engine's fuel needs vary. There is only ONE fuel line supplying the motor, and no return line. There is a fuel pressure dampner on the end of the fuel rail in place of a fuel pressure regulator. It's job is to absorb fuel presure waves and prevent wild flucuations in fuel pressure as the pump varies it's rate of flow attempting to match engine demand. The Fuel pump is controled via it's own built in fuel pressure regulator and via the ECU. When you apply the throttle, the ECU sends the signal to the fuel pump to increase flow, in time with throttle position. The fuel pressure regulator built into the pump can "over-ride" the ECU signal to prevent fuel pressure spikes or dips.
The Advantage of a "returnless" fuel system is that it is more compact, lighter and more efficent (thermally and electrically)
The disadvantage is that returnless systems are much, much harder to modify. Because the fuel pressure is set within the pump itself, and controled via the ecu. Modifications to both are required to increase fuel pressure/flow.
The switch to returnless fuel systems has been made for emissions reasons, not for fuel economy reasons. Heating the fuel causes the lighter hydrocarbons to evaporate out. The returnless system does not put as much heat into the fuel, so not as much evaporation occurs.
Switching to a returnless system is not an option. You would need to replace the pump, the hosing, the ECU and the fuel rail. It's just not feasable.
Beta1's are all "return" based systems. Some Beta2's are "returnless" and some are 'return' systems. In general, the Beta2's in the USA are returnless.</div>
i know it's an old topic, but... does anybody have some pics of conversion from returnless to return system? I have an accent(which i believe has a returnless system), with a beta 1 engine inside(for which you said has a RETURN system.) when i was swapping, i haven't noticed ANY return system from the beta1!! how come you claim it it return? i can also post a pic of what i think!
http://shrani.si/o.php?img9179fpr1078520.jpg
thaaank you!!
Igor
The "normal" Fuel Pressure regulator maintains fuel pressure of about 43psi (little less at times of high vacuum, but about 43psi at atsmopheric pressure(wide open throttle)). The fuel pressure regulator allows enough fuel to "bypass" the regulator to keep the pressure at the proper level. The bypassed fuel returns to the fuel tank via a seperate, yet paralell line next to the primary feed line.
The advantages of a "return" style fuel system is that it allows you to run basically any size fuel pump (as long as it is big enough to meet engine demand). You can run a 150 LPH pump or a 300 LPH pump. The Fuel Pressure regulator does it's job bypassing the extra fuel. It's also very simple to setup, and fairly simple to modify.
The disadvantages of a "return" style fuel system is that it heats the fuel. Anytime you pressurize something, you heat it. So the return system of constantly recycling/pressurinzing more fuel than is needed heats the gas. Running the gas through the hot engine compartment time and time again also heats the fuel.
"Returnless" systems are very different. The fuel pump has it's own pressure sensor built into the pump. It speeds up and slows down as the engine's fuel needs vary. There is only ONE fuel line supplying the motor, and no return line. There is a fuel pressure dampner on the end of the fuel rail in place of a fuel pressure regulator. It's job is to absorb fuel presure waves and prevent wild flucuations in fuel pressure as the pump varies it's rate of flow attempting to match engine demand. The Fuel pump is controled via it's own built in fuel pressure regulator and via the ECU. When you apply the throttle, the ECU sends the signal to the fuel pump to increase flow, in time with throttle position. The fuel pressure regulator built into the pump can "over-ride" the ECU signal to prevent fuel pressure spikes or dips.
The Advantage of a "returnless" fuel system is that it is more compact, lighter and more efficent (thermally and electrically)
The disadvantage is that returnless systems are much, much harder to modify. Because the fuel pressure is set within the pump itself, and controled via the ecu. Modifications to both are required to increase fuel pressure/flow.
The switch to returnless fuel systems has been made for emissions reasons, not for fuel economy reasons. Heating the fuel causes the lighter hydrocarbons to evaporate out. The returnless system does not put as much heat into the fuel, so not as much evaporation occurs.
Switching to a returnless system is not an option. You would need to replace the pump, the hosing, the ECU and the fuel rail. It's just not feasable.
Beta1's are all "return" based systems. Some Beta2's are "returnless" and some are 'return' systems. In general, the Beta2's in the USA are returnless.</div>
i know it's an old topic, but... does anybody have some pics of conversion from returnless to return system? I have an accent(which i believe has a returnless system), with a beta 1 engine inside(for which you said has a RETURN system.) when i was swapping, i haven't noticed ANY return system from the beta1!! how come you claim it it return? i can also post a pic of what i think!
http://shrani.si/o.php?img9179fpr1078520.jpg
thaaank you!!
Igor
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Joined: Sep 2002
Posts: 2,236
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^^
your in europe. he should have pointed out that all american beta1's have a return fuel set up, other country's beta1's that were map based had returnless set ups. but here in america, we all have maf/return set up's
your in europe. he should have pointed out that all american beta1's have a return fuel set up, other country's beta1's that were map based had returnless set ups. but here in america, we all have maf/return set up's
Junior Member
Joined: Dec 2006
Posts: 24
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Vehicle: hyundai accent 1996
<div class='quotetop'>QUOTE (xxxmonoxidechild @ Nov 13 2006, 10:52 PM) <{POST_SNAPBACK}></div><div class='quotemain'>^^
your in europe. he should have pointed out that all american beta1's have a return fuel set up, other country's beta1's that were map based had returnless set ups. but here in america, we all have maf/return set up's</div>
aha! and how is it with map, if i convert my returnless system to the return one?
your in europe. he should have pointed out that all american beta1's have a return fuel set up, other country's beta1's that were map based had returnless set ups. but here in america, we all have maf/return set up's</div>
aha! and how is it with map, if i convert my returnless system to the return one?
