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stock lift pump, bigger lines.

1332 Views 8 Replies 7 Participants Last post by  12valvefirefighter
Now this is just an idea. if i ran bigger fuel lines from the pump to the filter and filter to injection pump, would that create less of a pressure drop? that and personally i think volume is more important then pressure itself. just a thought. has anyone done any mods to the stock pump, and gotten better fuel flow? thanks RK
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the problem is still the fact that the factory LP is a better pusher pump than a sucker....which is why dodge offered the retro fit intank pump to replace the junk setup they had always ran...

volume and pressure are both important....yeah, you need the volume, but you need a minimum presure to keep the VP happy...
ya maybe i'll just bite the bullet at get a REAL pump
yeah...i mean AIRDOG has there special going on right now, but IMO--at least do what i did and got just the pump from FASS...the HPFP 95....that way i still use my factory fuel filter housing,but i need to get a big line kit and run it from my filter housing to my VP...with just my stack i can go to WOT and pull the pressure down to 9....
The larger diameter lines will not help. The problem is that the factory pump (no matter pushing or pulling) SUCKS!
Considering my truck has a few miles on the odometer (170,000) I did not want to spend a ton of money and time with the install of the big Airdog or Fass pumps. As long as you don't plan to any big power upgrades, just go with the Fass DDRP (Direct Dodge Replacement Pump). It was easy to install and fixed the low pressure problem.
Either way, good luck.
Larger banjo bolts will help flow. But the factory LP setup still... Sucks. Pardon the pun. :(
Guys, you keep missing the mechanical failure. There is a plastic piece that connects the motor to the pump. It breaks without warning. That's the number one reason to never use the factory lift pump.
I tried 1/2" lines from the pump to the fuel canister with the stock (in tank) LP and the fuel pressure just dropped to about 1 PSI upon start-up. With the stock lines it was showing 11-12 PSI at idle, and with the Raptor and the 1/2" line its around 16-18 PSI.
Do not waste your time or money looking for band-aid fixes, do it right the first time and get a Airdog/Raptor or FASS unit, they are worth every penny.
so thats what happened to me? the plastic piece broke that impller peice off the motor. Cause i can hear it on but my fuel filter housing is dry.:shock:
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