rail pressure low

[JWadford]

i have two dodge style cp-3 pumps, i have a stage 2 industrial injection pump with dual feed line on the bottom, and the belt driven one on top is stock, the bottom pump is dual feeding the rail while the top pump is feeding through the pressure sensor port the rail pressure sensor is on the top pump, tst completely removed from truck, mp-8 at about 30% and smarty on 3, timing on 3, rail press two, and tq management on wild, wide open throttle can only make 17000 psi rail pressure, also running 63 litre bfi injectors, and twins set to 70 psi egts go past 1600 deg pretty fast which i think is from low rail pressure, the stage two pump all by itself can almost flow that much, is there a way to test the top pump all by itself without taking it off, although taking it off is only about a 10 min job, but then i would have to ship it to industrial injection to get checked out, or should i put the rail pressure sensor back in the rail and hook the dual feed line to the top pump and see what happens, also truck doesnt feel like its making much more than around 650 h. p. i was under the impression with dual pumps the rail pressure would stay where you needed it, level 3 on the smarty is not alot of tune and neither is 30%of mp-8 i know my injectors are kinda big but they arent that big, maybe i need a stage 3 dmax pump on top???

 

[WoodChuck]

Did your setup work as expected after installed and then at a later date start acting up? How are you reading rail pressure, is it plugged into the sensor before the MP8?

 

[JWadford]

Did your setup work as expected after installed and then at a later date start acting up? How are you reading rail pressure, is it plugged into the sensor before the MP8?

Rail press is read right off the sensor via quadzilla, and i have had this issue since the install and i have around 50 miles on it

 

[WoodChuck]

Maybe it's defueling as a result of the high EGTs. Try taking off all the power adders first and them add them in slowly one at a time. You should be able to get at least 23,000 psi. and maintain it.

 

[TCDiesel]

1st do you have our modded rail?. You are not the 1st to have this issue when trying to feed the rail from top and bottom... they are those that have the dual pump setup and trying to feed the rail from opposing forces... also taking the pressure reading from points other than the rail are somewhat off... All you top and bottom manufactures Bring it on!!. . it's this simple. . the top and bottom does work, it's just not the best way to feed the rail and injection system. Jwadford if you need to attack this problem why not just look into re-plumbing to the dual bottom feed?

 

[JWadford]

Maybe it's defueling as a result of the high EGTs. Try taking off all the power adders first and them add them in slowly one at a time. You should be able to get at least 23,000 psi. and maintain it.

i dont have anything on my truck that will defuel by egt

 

[JWadford]

1st do you have our modded rail?. You are not the 1st to have this issue when trying to feed the rail from top and bottom... they are those that have the dual pump setup and trying to feed the rail from opposing forces... also taking the pressure reading from points other than the rail are somewhat off... All you top and bottom manufactures Bring it on!!. . it's this simple. . the top and bottom does work, it’s just not the best way to feed the rail and injection system. Jwadford if you need to attack this problem why not just look into re-plumbing to the dual bottom feed?

i need lines and fittings for the dodge pump on top, and i plan on trying one of your rails, just havent done it yet

 

[lmills]

TWest, I honestly mean this with respect, we are going to put the discussion on single feeding and dual feeding the rail to bed very shortly. We have a close friend that is making over 1K on fuel with an 04 truck running the PPE kit that cannot maintain rail pressure with their single feed set up. We have sent him a line to use so he can dual feed his rail. I will let you know the honest results of how it turns out.

My personal thoughts are that he will be able to maintain pressure and make more power. Sounds to me like you are saying it will lose power. Am I correct in this assumption?? The test rig has numerous runs over 1K on a dynojet 248 for the test equipment.

 

[JWadford]

TWest, I honestly mean this with respect, we are going to put the discussion on single feeding and dual feeding the rail to bed very shortly. We have a close friend that is making over 1K on fuel with an 04 truck running the PPE kit that cannot maintain rail pressure with their single feed set up. We have sent him a line to use so he can dual feed his rail. I will let you know the honest results of how it turns out.



My personal thoughts are that he will be able to maintain pressure and make more power. Sounds to me like you are saying it will lose power. Am I correct in this assumption?? The test rig has numerous runs over 1K on a dynojet 248 for the test equipment.

do i need smaller injectors to raise rail pressure or should i go with a stage 3 dmax pump and nitrous, i want to join the 1000h. p. club i know which wont happen without nitrous or a trick head, i mean my truck runs strong but like i said rail press drops to about 17000 and when i let out it hits 25000, maybe my top fca is sticking, but not sure, i raced a so called 600 h. p. duramax with 265 tires and i would only put four truck lengths on him and then he would hang, my truck is turning 100 lb rim combined 37s i dont think my truck is where it should be, also i was running both stages of snow with the big nozzles, im sure it would be alot faster with smaller tires

 

[lmills]

Most of the trucks currently making over 1000 on fuel are using stock heads and stock cp3's. One is dual feeding the rail and making over 1100, the other is pulling his rail pressure down from 27K to 21K on a hard run and making 1070.

It can happen without nitrous or an aftermarket ported head. To check to see if the FCA is sticking, unplug it while running and see if pressure ramps up. Do not let it run continuously like that though.

Putting the rail sensor back in the rail and running the second line from the top pump into the rail would not hurt to try. I have never had a problem making power feeding the rail in 2 places with separate pumps, but we have gotten numerous mixed reviews about running dual feeds on single pumps. Some trucks seem to respond well to them, others do not. You have to consider the pulses of the fuel coming in and out of the rail and how it affects the fuel delivery. With the rail being fed in 3 places, you have now added on more piece to the equation

oh yeh, what are you running for air flow???

 

[JWadford]

piers twins 40/3b at 70 to 75 psi and i was unsure of unplugging the fca for fear of damage running both pumps at the same time, i have done it with one, but with two i wasnt sure if unplugging one of the fca's would hurt anything

 

[TCDiesel]

TWest, I honestly mean this with respect, we are going to put the discussion on single feeding and dual feeding the rail to bed very shortly. We have a close friend that is making over 1K on fuel with an 04 truck running the PPE kit that cannot maintain rail pressure with their single feed set up. We have sent him a line to use so he can dual feed his rail. I will let you know the honest results of how it turns out.



My personal thoughts are that he will be able to maintain pressure and make more power. Sounds to me like you are saying it will lose power. Am I correct in this assumption?? The test rig has numerous runs over 1K on a dynojet 248 for the test equipment.

Imills, We do not measure anything on the dyno. . The Dyno Means absolutely nothing to Me, it's only a few second event... T&C measure the long term effects of the entire injection system. . We would like to see the system last the entire life of the engine ( life expectancy) Injectors are extremely sensitive in 3 gens engine... HP to Me is secondary when you sacrifice the engine to gain it. . Most owners would like to say away from the wallet suck up devices. . The only thing that separates Me from building a 1000 HP + is I don't want to. . My Capital and resources are you use to serve the diesel Enthusiast. We don't hang are achievements Like a Cow Bell.

Lloyd if someone wants a dyno Queen I suggest they look you up, But there is a huge market for the 500/700 hp owner that would like to have the friendly operating truck also, In today's market it's not how much HP you can make, It's how you can make AND make it last.

 

[lmills]

I guess I am better suited for this discussion then. After all this guy is looking for 1K which you in your own words believe is a waste. And in your own words he would be better off to deal with me on his "dyno queen. "

Lastly, I mentioned the dyno for the sole aspect that we need something to measure how the fuel delivery is holding up. I am sure you realize that dynos can be loaded to simulate a 1/4 mile run, correct? You say it doesn't work, I am willing to put it on the line that you are incorrect. Which is exactly what will happen when I supply the second line to the tester if it doesn't work.

Lastly, my dyno queen towed another truck 800 miles to TS, not once, but two years now. Hardly a dyno queen. It also has over 100K miles on it, which is something some guys have not been able to achieve with a truck with just a chip. I think I have proven myself over and over and do not owe you anything. Not to mention I should also state that since you are worried about longevity, I have only ever damaged one injector. And that was from insane rail pressure at an event.

So, with your supreme level of expertise maybe you would like to tell me all the ill affects I am going to experience by not running your rail, or from feeding the rail in two spots, or from not using snake oil additive? I also find it funny that you should stereotype some like a young uneducated person would. Yes the blue truck has been mostly a dyno truck, but do you think you could handle racing a 6 speed truck at that level of power? I have trucks that we have built for customers that race and sledpull. So with that I ask, what exactly have you done to promote diesel motorsports other than criticize every post I make?

 

[JWadford]

Okay, enough arguing and back to buisiness,everyone needs a little contructive criticism every now and again but that is what keeps things getting better, so i will test the fca and if that isnt the problem, then i will move the sensor back to the rail but that might not show much of a difference, i would like to know whos injectors and what size these people are running maybe mine are too big, they do haze at idle

 

[WoodChuck]

Give the guys at Brown's Diesel a call, they have lots of experience with high power diesels.

 

[TCDiesel]

63s should work well with twins. . Know of a couple race twins running 65s no complaints. the haze seems to be normal with 60+.

 

[JWadford]

now i feel like a dumb___!!!! i unplugged the top fca and the rail pressure did not go up at low idle , if i unplugg the bottom one, watch out it peggs the guage... . so looks like when i get a minute, i will pull the fca off and see if it is plugged or just stuck

 

[lmills]

glad to see it wasn't from dual feeding the rail with the dual pumps!

 

[JWadford]

actually triple feeding the rail lol

 

[TCDiesel]

now i feel like a dumb___!!!! i unplugged the top fca and the rail pressure did not go up at low idle , if i unplugg the bottom one, watch out it peggs the guage... . so looks like when i get a minute, i will pull the fca off and see if it is plugged or just stuck

Exactly My Point... That why we recommend the sensor on the rail.