Jump to content
Mopar1973Man.Com LLC

  • Welcome To Mopar1973Man.Com LLC

    We are a privately owned support forum for the Dodge Ram Cummins Diesels. All information is free to read for everyone. To interact or ask questions you must have a subscription plan to enable all other features beyond reading. Please go over to the Subscription Page and pick out a plan that fits you best. At any time you wish to cancel the subscription please go back over to the Subscription Page and hit the Cancel button and your subscription will be stopped. All subscriptions are auto-renewing. 

Fuel Pressure spread

notlimah
 Share

Recommended Posts

notlimah

notlimah

Posted
Posted

Hello all!

 

First time posting here, long time forum stalker!

 

I've recently installed a Raptor FRRP to replaced my failed carter. Not sure how long that one was out but I found out while in the process of installing my ISSPRO gauges.

 

Right now once the truck is fully warmed up my fuel pressure is at 19psi sometimes falling just into 20psi.

While running down the road my numbers are between 16-18psi depending on hard heavy the left foot is.

At WOT I get 14psi, sometimes dipping down to 13psi.

 

While from the research I've done from this site, the numbers I'm seeing fall well within the safe zone of the vp44, I'm a little concerned about the amount it's dropping between idle and WOT. Ideally I'd like to get it down to no more then +/- 5psi.

 

On top of the FRRP, I've also installed the vulcan big line kit. I'm sort of thinking it could be my stock fuel line coming from the tank to the raptor that is causing this drop, but I'm far from an expert, so that's what I'm hoping to get help with!

 

Thanks in advance!

 

Matt

Link to comment
Share on other sites
Ilikeoldfords

Ilikeoldfords

Posted
Posted

Like Mike said, I would make sure that everything from the tank to the injection pump is at least 3/8's inch or bigger. That includes all the fittings too. One question, when was the last time the fuel filter was changed? It might be plugged up causing a restriction.

 

I was having a pretty bad pressure drop like that when I installed my raptor pump. I recently installed a fuel tank sump and all my pressure drop issues went away. The stock sending unit inside the tank was causing a big restriction in my case.

 

Something to think about.

 

Here is the tank sump that I used.....    Tank Sump.

 

Really great product too.

Link to comment
Share on other sites
Dieselfuture

Dieselfuture

Posted
Posted (edited)

or make sure you modify your fuel module and make outlet and return as big as you can. even that 3/8 clip on module fitting is supposed to be 3/8 but it's only 5/16 on id plastic 90's to fuel module and some places in side is down to 1/4 :wow:

post-1102-0-13090100-1424662027_thumb.jp

Edited by Dieselfuture
Link to comment
Share on other sites
notlimah

notlimah

Posted
  • Author
Posted

Stock lines can't flow fuel good enough to keep the pressure up. So it would help to convert over any remaining stock lines.

 

AirDog / Raptor pumps have a low quality as most members will tell you.

 

Yea, I knew that going with the FRRP I would be selling myself short a bit but I didn't have the money to spend on a higher quality system at the time. Ultimately I would like a FASS Titanium system! Would getting something like Vulcan's relocation kit help my situation?

Link to comment
Share on other sites
notlimah

notlimah

Posted
  • Author
Posted

Like Mike said, I would make sure that everything from the tank to the injection pump is at least 3/8's inch or bigger. That includes all the fittings too. One question, when was the last time the fuel filter was changed? It might be plugged up causing a restriction.

 

I was having a pretty bad pressure drop like that when I installed my raptor pump. I recently installed a fuel tank sump and all my pressure drop issues went away. The stock sending unit inside the tank was causing a big restriction in my case.

 

Something to think about.

 

Here is the tank sump that I used.....    Tank Sump.

 

Really great product too.

 

The fuel filter was just changed with the lift pump less than 100 miles ago, although that was just with a WIX filter, I've heard mixed reviews of those as well.

 

So with the tank sump, you just drain your tank, drill a hole and install that bad boy, hook up your fuel line and your good to go? I'm not familiar with that particular upgrade.

Link to comment
Share on other sites
notlimah

notlimah

Posted
  • Author
Posted

or make sure you modify your fuel module and make outlet and return as big as you can. even that 3/8 clip on module fitting is supposed to be 3/8 but it's only 5/16 on id plastic 90's to fuel module and some places in side is down to 1/4 :wow:

 

I'll definitely keep this in mind, but I'd rather not have to pull all that out of the tank! ha!

 

 

The old school method.

2rzfo1j.jpg

 

That looks like my kind of mod! :thumbup2:

Link to comment
Share on other sites
TFaoro

TFaoro

Posted
Posted

Welcome! I personally like the fass sump with the straw coming out the top, but it is pretty pricey. You're fuel drop is because of the small lines. I have the stock line between the fuel filter and the injection pump and can pull it down 10psi. When funds are there I will make some changes.

Link to comment
Share on other sites
notlimah

notlimah

Posted
  • Author
Posted

Welcome to the forum!

 

 

Welcome! I personally like the fass sump with the straw coming out the top, but it is pretty pricey. You're fuel drop is because of the small lines. I have the stock line between the fuel filter and the injection pump and can pull it down 10psi. When funds are there I will make some changes.

 

Thanks for the welcome fellas! This is a great forum!

 

I'm going to give Eric @ Vulcan a call and see what I can work out as far as getting bigger lines from the tank to the lift pump. I might just get the relocation kit and move my FRRP back, that way when I upgrade it'll be an easier swap.

Link to comment
Share on other sites
rancherman

rancherman

Posted
Posted

Thanks for the welcome fellas! This is a great forum!

 

I'm going to give Eric @ Vulcan a call and see what I can work out as far as getting bigger lines from the tank to the lift pump. I might just get the relocation kit and move my FRRP back, that way when I upgrade it'll be an easier swap.

you'll find  the  frrp will do a much better job at pushing the fuel thru  the   small lines  rather  pulling it.  (heck any pump  does  that)

Plus you'll  have  the  frrp  away from  the hot and  vibrations  of  the engine...( the  caveat to this is   a   REALLY   cold location for the  pump's intake  screen)

 

my current  cobbled up configuration (CCC) is    a  Fass  drp 02  in stock location, stock lines  from tank,  big line kit left over  from previous failed FRRP .. and  a   100  micron  screen  right beside the  starter.    When  that  jells  up..   its  easy to  throw the hood open,   and  blast it with the heat gun..  Sometimes  I luck out and am only  15 miles  from home!

Keep in mind,   we are all on   borrowed time with  any of these  pumps.  So   start  your   research now  what will be the next  'best gosh dang  fix'.   Good luck and  welcome to the fray.

Link to comment
Share on other sites
notlimah

notlimah

Posted
  • Author
Posted

you'll find  the  frrp will do a much better job at pushing the fuel thru  the   small lines  rather  pulling it.  (heck any pump  does  that)

Plus you'll  have  the  frrp  away from  the hot and  vibrations  of  the engine...( the  caveat to this is   a   REALLY   cold location for the  pump's intake  screen)

 

my current  cobbled up configuration (CCC) is    a  Fass  drp 02  in stock location, stock lines  from tank,  big line kit left over  from previous failed FRRP .. and  a   100  micron  screen  right beside the  starter.    When  that  jells  up..   its  easy to  throw the hood open,   and  blast it with the heat gun..  Sometimes  I luck out and am only  15 miles  from home!

Keep in mind,   we are all on   borrowed time with  any of these  pumps.  So   start  your   research now  what will be the next  'best gosh dang  fix'.   Good luck and  welcome to the fray.

 

That's what I'm hoping to achieve! I like my idle and cruising psi readings, I DON'T like the drop from idle to WOT so, hopefully moving that further back away from everything you mentioned, on top of bigger fuel lines with alleviate that!

Link to comment
Share on other sites
Hawkez

Hawkez

Posted
Posted

You could always put the money in a Fuel Boss.  I don't see any pressure fluctuations with my mechanical pump.  Idle and WOT are the same, as stead 17 PSI.  My supply line coming from the tank to under the driver's seat is stock. From there it is 3/8 to the Fuel Boss and then on to the IP. 

Link to comment
Share on other sites
Ilikeoldfords

Ilikeoldfords

Posted
Posted

The fuel filter was just changed with the lift pump less than 100 miles ago, although that was just with a WIX filter, I've heard mixed reviews of those as well.

 

So with the tank sump, you just drain your tank, drill a hole and install that bad boy, hook up your fuel line and your good to go? I'm not familiar with that particular upgrade.

 

No need to drop the tank or anything. I just used the electric lift pump to basically run the tank dry into a couple fuel cans. Drill the hole in the tank, and mount her up!! Very simple. The whole thing didn't take more than 30 minutes to do. The most time consuming part is draining the tank.

 

Here is their video on the installation.        Youtube

Link to comment
Share on other sites
Hawkez

Hawkez

Posted
Posted

How hard is the swap from electronic to mechanical fuel pumps?

Pretty simple. I bought the fuel boss from GDP and they have detailed insructions. You can read through those instructions on their web site. It was a two hour install for me.

Link to comment
Share on other sites
AGPTurbo

AGPTurbo

Posted
Posted

Hawkez, IBMobile, and CT if you're out there, since you guys brought it up, how many miles would you guys say you have on the Fuel boss? I am happy with my airtex in the stock location but after I install the rest of my gauges (fuel pressure was put on a year ago) and I add a comp or ez, I'm going to get the boss. I love the redundancy of the stocker for backup since we do PA to Florida twice a year.

Any input would be appreciated.

Link to comment
Share on other sites
 Share
Go to topic listing
×
×
  • Create New...