What size big line kit do I need?

[JAG1]

I like my big line kit because it allowed me to add my own flow restrictions. :)Such as.:Racor W/S filter before the lift pump.Ball shut off valves either side of the lift pump and prefilter for easy change out of filters and lift pumps.Hauling heavy uphills and having the stock filter restrictions. (after the lift pump).Plus Eric at Vulcan performance demonstrated to me how much an improvement it was over the stock lines. I had a new fuel psi gauge put on just before he and I changed everything out. Just the 1/2 inch draw straw alone showed a 1 psi improvement.Back then this was all on a new stock pump moved to the frame.

[Wild and Free]

I like my big line kit because it allowed me to add my own flow restrictions.

Such as.:

Racor W/S filter before the lift pump.

Ball shut off valves either side of the lift pump and prefilter for easy change out of filters and lift pumps.

Hauling heavy uphills with still having the stock filter restrictions (after the lift pump).

Plus Eric at Vulcan performance demonstrated to me how much an improvement it was over the stock lines. I had a new fuel psi gauge put on just before he and I changed everything out. Just the 1/2 inch draw straw alone showed a 1 psi improvement.

Back then this was all on a new stock pump moved to the frame.

I was waiting on someone to touch on this, it is a whole other subject, Bigger suction lines are good too "To a Point" They should be a size bigger than the lines you are feeding, " this too depends on weather it is a scavenge or gravity fed pump and weather or not the liquid source is under pressure or at atmospheric or slight vaccuum but it too comes down to pump capabilities as is everything else we are talking on and as you pointed out we need to bring up a point of pumps now, The factory pump was designed to fail as it was designed as a pusher pump and was not intended to "Scavenge" for fuel it was supposed to be as close to the tank as possible. Had it been a gravity fed pump or at least close to the fuel level and not engine mounted they would have been much more reliable.

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Moparman says I need a big line kit with my raptor 100 on my 2001 stock Dodge. How big? Big lines all the way to the injection pump? I know about the high flow banjo bolts but are there big line banjo fittings? I am thinking about the XDP sump instead of a larger draw straw. Any thoughts on that? Can I still use the stock fuel filter?

Sorry for derailing the thread and not directly answereing the poor guys basic question.

Get the banjo bolt upgrades and get the line kit between the filter and Vp44 use the stock filter with a 7 micron fleetgaurd filter which is all you can get from Mopar now and sit back and relax and be glad you saved a few buck and didn't spend anymore money and waste your time on things you don't actually need.

I ran a Fass HPFP150 "Overkill, a 95 would have been way more than enough" for about 8 years and ran it off the factory intake off the top of the tank and never once had an issue with fuel pressure, Had 3/8 line all the way but did get the 1/2 inch line kit between the filter and vp but that was more so for the ease of adding things like sensors and switches ect. I was at 560 hp for reference and competed in racing and powerpulls and never once ran out of fuel with an unloked Hot comp HRVP44 and 155 sticks.

[JAG1]

I was waiting on someone to touch on this, it is a whole other subject, Bigger suction lines are good too "To a Point" They should be a size bigger than the lines you are feeding, " this too depends on weather it is a scavenge or gravity fed pump and weather or not the liquid source is under pressure or at atmospheric or slight vaccuum but it too comes down to pump capabilities as is everything else we are talking on and as you pointed out we need to bring up a point of pumps now, The factory pump was designed to fail as it was designed as a pusher pump and was not intended to "Scavenge" for fuel it was supposed to be as close to the tank as possible. Had it been a gravity fed pump or at least close to the fuel level and not engine mounted they would have been much more reliable.

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My stock pump was on the frame near the tank. I had two failed lift pumps in 35,000 miles time.

I don't think this thread is derailed because all of this information is related and affords some background or surrounding information that is important.

As far as having more flow thru the filters... that is a good thing because the more flow the more fuel polishing effect you have with return fuel. This is why I'm considering bigger return lines instead of the 3/16ths factory line.

[Wild and Free]

You'll have to explain this one to me, never heard of this terminology,

Remember that the more fuel going to return the more heat generated in the system and this directly affects pump and system efficiency due to the thinning of the fluids which directly affects flow and pressure.

Folks are forgetting the basics here that the temperature of things and especially the fluid being pumped will directly affect the pressures depending on how effecient your components are especially the pumps.

Folks need to stop worrying about .5-even a couple psi change in systems unless you are already at the minimum allowable specs required. If you are dealing with 3-4+ psi changes you now have issues that need to be addressed but nothing to worry about if less that that.

Flow, pressure, resistance to flow or restrictions.

the pump generates flow, all the components in a system generates restrictions or resistance to flow which is what creates pressure. all of these events cause heat, heat thins fluids and thus will test how efficient your system is, if the pump is worn and it flows cooler thicker liquids fine with good pressure and then things heat up fluids thin and the pump now has internal leakage of even check valves or any other device that restricts flow and the restriction lessens on a properly specs system then your pressures will drop as the flow or restristions drop. I could go on for pages because there are too many variable to talk about but It should give folks a good idea where I am headed. "bigger lines will not be the answer here"

Years ago there was a long running thread on one of the original Dodge Cummins sites "TDR" with years of experimenting and testing and mods to keep the Vp44 and fuel cooler and this after years turned out to be a very good thing and backed up the basic theory of pump efficiency and longevity and the law of physics of fluids and how temperature plays into things ect.

It has been a few years since I checked in over there but it was among the longest threads there for years.

[JAG1]

Thanks Wild and Free, I read that thread too. It was lengthy but very interesting with their remote temp sensors everywhere on the lines, testing VP temperatures and using fuel coolers.One of the close buddies to the two guys doing the tests on that thread told me I needed to increase the size of the return line. Now for what exact reasons... I cannot remember. He said he had already completed that mod on his truck. This where my idea came fromFuel polishing to the extreme is adding fuel line and another lift pump to cycle fuel thru added filters. The term came from larger yachts because the fuel sits all winter and needs added filtering.Are you saying the the fuel in the tank wil eventually get too hot?

[Wild and Free]

Are you saying the the fuel in the tank wil eventually get too hot?

In the right conditions it will get fairly warm, probably not hot unless the level gets fairly low then it would probably get warmer depending on ambient temps and speed of travel ect.

[oldbeek]

I started this post because I was getting a 10psi pressure drop at hard pull, with a VP100 raptor pump and stock lines and filter. This problem popped up after replacing the Raptor on warranty. I always say go back to the basics but guess I am getting senile.:doh: I could have a restricted fuel filter causing the problem. Anyway great discusssions. What I did find is the fitting going into the VP44 weather banjo fitting or 12mm JIC adapter is only .297 dia. with( .0692) sq in area. The restricted banjo bolt with 4 .130 holes has .0530 area The banjo fitting at tubing connectoin is .173bore with an area of .02349 in, A whopping 33% smaller than the banjo bolt bore. The stock fuel line has .07666 area, 10% larger than the banjo bore. 3/8 line area is .1104 in area which is 37% larger than the banjo bore area. With distance adding resistance being a factor , I think 3/8 line is in order with 3/8 banjos and hi flow bolts. Also I had better check fuel pressure befor and after the fuel filter

[JAG1]

I used to get that much pressure drop with the stock lines. With the 1/2'' lines ( stock pump on the frame) I was getting a steady 14. Could not drop the pressure no matter what. Later with the big drawstraw I gained 1 psi steady.Whatever pumps we are using, does not work as hard with bigger flowing fuel lines. JMHO . I think all trucks need a prefilter and the hot return fuel moved away from the fuel supply so hot fuel isn't getting returned back to the VP. I read all this in the TDR thread mentioned. I moved the return line to dump down the filler neck.Also you should use nylon washers or whatever to get the stock filter off the manifold. There's a lot of heat going to the fuel when the filter housing gets too hot to touch. Just another bit of info from the TDR guys. I made a bracket out of fireproof plastic to hold an inch away.

[AH64ID]

As W&F noted were making a bigger deal out of this than needed, but it's a fun discussion so why not :-)I want to touch on the fuel polishing effect, yes it's good as you fuel is filter more than it would normally be. But it's my biggest beef with the AD/FASS setups that do it. The filters are not sized for the flow they get. A FASS 150 may only be pushing 70 GPH (arbitrary) to the injection pump, but the full 150 GPH is getting sucked thru thr f/w sep and whatever isn't needed to make the pressure set point is sent back to the tank. So you have 150 GPH being flowed thru a 90 GPH filter, maybe 120 GPH (some filters), but either way the flow is decreasing the efficiency of the filter and that's not a proper setup.The stock setup polishes the fuel plenty as well. On my 05 the pump is somewhere between 35-50 GPH under normal pressure, and about 90 GPH at no pressure. My average burn over the last 85K miles is about 2.15 GPH, so that's a lot of fuel polishing and it's all at a volume lower than the filters are rated for. When I replace the stock pump I will probably go 1/2" line from the tank, thru my first filter, and to the pump and then 3/8" line thru the next 2 filters to the CP3. There are lot's of people not running an over-sized suction, but I think it's a good idea.

[Mopar1973Man]

Without reading all this... I'm going to simple put it this way. It best to just run the 1/2" lines from tank to VP44 and be done with it. 1/2" line will have less restrictions and give less problems if you decided to upgrade late with more power or loads. Pressure is more stable with 1/2" than stock 6mm, or 3/8" lines. Yeah we can beat the whole line size with science and fact and figures but still 1/2" will always be the most stable fuel system pressure wise. Kind of like I've got a irrigation dam 1/3 of mile behind me. The pipe leaving the dam is 8" but necks down to 4" at the top of the mountain. Then there is a manifold and necks down to 1" to everyone's yards. I know the 8" pipe has a constant pressure that never changes regardless of how many sprinklers turned on. I'm sure there is a slight drop in the 4" but very little. But on my 1" line too many sprinklers and a pelton wheel generator running I can pull that 1" line down to 20 PSI for a static of 116 PSI.So getting back to the VP44. Bosch states that 70% of fuel volume should be return to the fuel tank for properly cooling and lubing. So roughly under the heaviest load you could require around 80-90 GPH of supply to meet the 70% return. So with larger lines the pressure loss will be less and cooling/lubing will continue.

[JAG1]

Just the fact that I experienced no pressure drop after installing the 1/2'' lines is great. Before I hated pulling away from a stop light and watching the pressure drop to 7. When I got down to Vulcan performance It was cool.... Eric helped me put the big line kit on in his driveway. I didn't even pay him yet when he says, ''Okay now, take it out for a run and get on it, tell me what you think''. I was very happy when everything I did would no longer let the pressure drop.Why the Raptor lets the pressure drop on take offs or hauling up steep hills I don't know other than it's pressure is much higher than the stock pump ever was to begin with.IMHO, The VP needs every benefit we can give it.Mike with what you say above..... Does that mean you think there might be some benefit to increasing the size of the return line then?

[Mopar1973Man]

Not really. Because the overflow valve is the limiting factor. With the check ball and the size of orfice I doubt there would be any gains to oversizing the return line. Then on top of that there is no need for exceeding 20 PSI because by 14 PSI the overflow valve is open and flowing strong.

[SNKEBIT]

You want to replace the banjoes with their tiny holes with full flow fittings like the JIC fittings that Vulcan offers. No point in doing half the job.

Have a link to those fittings?

[ISX]

Not really. Because the overflow valve is the limiting factor. With the check ball and the size of orfice I doubt there would be any gains to oversizing the return line. Then on top of that there is no need for exceeding 20 PSI because by 14 PSI the overflow valve is open and flowing strong. [ATTACH=CONFIG]4963[/ATTACH]

Can you expand with all that you know about that smaller hole? Mine does not have it, I just have the hole in the bottom leading to the 2 opposing holes that flow through the banjo fitting.

[oldbeek]

Have a link to those fittings?

Vulcan performance.

[Mopar1973Man]

Can you expand with all that you know about that smaller hole? Mine does not have it, I just have the hole in the bottom leading to the 2 opposing holes that flow through the banjo fitting.

Air Bleed... Mag x10

Let's say that a single strand of 14 AWG copper wire will not fit but a single strand of 16 AWG will... Not very scientific measurement but gives you an idea of size its very very small hole.

[Mopar1973Man]

Have a link to those fittings?

Here you go... Male fittings (JIC) http://www.vulcanperformance.com/JIC-AN-adapters-s/187.htm Female fittings (Push loc JIC) http://www.vulcanperformance.com/Pushlock-Fittings-s/186.htm