Attention: TDR Forum Junkies 
I thought about adding my thoughts in "pumps, lines and whatnot", but here goes.
If I get these "givens" wrong, I am sorry in advance.
#1 Restrictions in the fuel system should be reduced.
~The higher the bombing level, the more need for reduction.
#2 The stock lift pump in its stock location leaves something to be desired.
~Depending on Hp, a relocation of the stock pump (up to any wild pressure/volume pump or combo of pumps that gives one a warm and fuzzy feeling) as close to the tank as possible.
#3 How to wire the pump/pumps and route the lines has some latitude.
One of the reasons that so much has been discussed on this subject is the fact that fuel pressure on the VP44 side of the filter (and probably up stream) drops with WOT applications (The amount of drop increases with HP output, everything else being equal. )
I want to use the Carter HP4601 pump for sake of my example.
I think that the problem is actually fuel momentum (or lack thereof). If one is just cruzing around at low throttle, the lift pump is internally bypassing a lot of its 110GPM capacity. One could allow the pump to not internally bypass by putting a regulator in the system as close to the VP44 as possible, set at a pressure below the internal pressure of the "lift pump", with a return line to the tank. Theoretically, the fuel in the line would be in motion at the 110 GPM flow rate (assuming all of the lines, fittings and whatnot were of adequate size). When a person Jabbed the throttle (WOT) the fuel would already be traveling as fast as the system would allow, and would continue on into the VP44 instead of through the bypass. (OK, so the Vp44 cant handle 110 GPM, but bear with me here. ) The "drop" in fuel pressure with the normal system is caused by having to start all of that fuel in motion.
I kind of "put my money where my mouth is" by installing a farmered up version of this on my 99. I installed my bypass (actually only an orifice, not a regulator) in ther pre-filter port of the fuel filter (different reason). I teed into the return line just aft of the engine. I can only get a 2-3 lb pressure drop under the worst of conditions (that is with an open orifice in the system). Those with bigger everything (HP, lines, pumps, whatnot and a pressure regulator) should achieve the same type of results with a similar system.
I was just rereading another thread and another thought came to me. If the lift pumps are going out because they are better pushers than suckers, having this kind of bypass would only make the pump (in its stock location) have to start the fuel in the system moving once at each start-up. May lenghten the life of a stock pump in stock location.
If I get these "givens" wrong, I am sorry in advance.
#1 Restrictions in the fuel system should be reduced.
~The higher the bombing level, the more need for reduction.
#2 The stock lift pump in its stock location leaves something to be desired.
~Depending on Hp, a relocation of the stock pump (up to any wild pressure/volume pump or combo of pumps that gives one a warm and fuzzy feeling) as close to the tank as possible.
#3 How to wire the pump/pumps and route the lines has some latitude.
One of the reasons that so much has been discussed on this subject is the fact that fuel pressure on the VP44 side of the filter (and probably up stream) drops with WOT applications (The amount of drop increases with HP output, everything else being equal. )
I want to use the Carter HP4601 pump for sake of my example.
I think that the problem is actually fuel momentum (or lack thereof). If one is just cruzing around at low throttle, the lift pump is internally bypassing a lot of its 110GPM capacity. One could allow the pump to not internally bypass by putting a regulator in the system as close to the VP44 as possible, set at a pressure below the internal pressure of the "lift pump", with a return line to the tank. Theoretically, the fuel in the line would be in motion at the 110 GPM flow rate (assuming all of the lines, fittings and whatnot were of adequate size). When a person Jabbed the throttle (WOT) the fuel would already be traveling as fast as the system would allow, and would continue on into the VP44 instead of through the bypass. (OK, so the Vp44 cant handle 110 GPM, but bear with me here. ) The "drop" in fuel pressure with the normal system is caused by having to start all of that fuel in motion.
I kind of "put my money where my mouth is" by installing a farmered up version of this on my 99. I installed my bypass (actually only an orifice, not a regulator) in ther pre-filter port of the fuel filter (different reason). I teed into the return line just aft of the engine. I can only get a 2-3 lb pressure drop under the worst of conditions (that is with an open orifice in the system). Those with bigger everything (HP, lines, pumps, whatnot and a pressure regulator) should achieve the same type of results with a similar system.
I was just rereading another thread and another thought came to me. If the lift pumps are going out because they are better pushers than suckers, having this kind of bypass would only make the pump (in its stock location) have to start the fuel in the system moving once at each start-up. May lenghten the life of a stock pump in stock location.
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