hoehand

I am pretty sure I am draining my rail. My question though, is it more likley to drain it when you hammer on it from a stop, or slow speeds. Or is it more likely to happen when you are running down the highway, and decide to pass someone.

My new stack seems like it is hitting a flat spot at full throttle at slower speeds, but does not seem to have the same issue when cruising.

Waiting on Quads monitor before doing much testing, but I am not sure it is a fuel pressure issue.

streetsmoker

With you mods, the fuel supply problem is not from the CP3 to fuel rail, it is in the Supply/Lift Pump. Any one of a number of aftermaket LP's can solve the problem. The general consensus is the factory CP3 doesn't run into rail pressure supply problems until around 600hp, or through the use of giant 100+hp injectors.

hoehand

I hope so.

That is what I want to try. Does it make sense that it would happen more at slow speeds? Who was it that was going to put together a kit for the walbro pump?

Green04HO

When it hits the flat spot do you hear a popping sound? Kind of like a popcorn popper. I get this sound with the quad race box. Only on the 140 setting and only if I smash the go pedal down. If I roll into it no noise. I also have plenty of LP pressure. Steady 15 PSI.

I have heard this noise refered to as "Bursting". It was first called this by the Duramax crowd I believe. If you do not have a fuel pressure gauge, I would recomend you get one ASAP. With just the race box I could pull the pressure down to 0 at will.

streetsmoker

Gypsyman is putting together the kits. He's still in the development stages, and can't say much about it till he get's his vendor privalages taken care of here. Just remember, I get the 1st one.

WUnderwood

streetsmoker-

gypsyman is putting together what kind of kit? a fuel system? can you share your info? thanks

streetsmoker

He's putting together a complete plug-n-play Walbro Lift Pump retrofit kit.

PapaSmurf

Hello all
A very good friend of mine ( one that I have been married to for 20 years) has a 2004 3500 HO with the auto trans. that was run on a dynoJet dyno @ 500 Hp and 968 Torq. When we dynoed the run was over so fast the fuel pressure only dropped down to 4 or 5 psi.

I do not agree with the above statement from streetsmoker. With a TSTpmcr stacked with a Edge ez in a quarter mile run she will suck the fuel pressure down to ZERO and yes the truck makes weird noises. The tst was on 4/6 and she left a bit of smoke at the starting line. I am currently researching a supplier to get a FASS for this truck.

I am not trying to start anything, I understand that each truck responses different. I am not familar with the boxes that hoehand has and I don't know what his HP/Torq range is, all I am saying is what I have seen with this truck.
I would strongly suggest you get a fuel pressure gauge for your truck, if you are adding a fueling box. The engine can't make any power if it isn't getting enough fuel.
See Ya
Chris

streetsmoker

You just gave the same answer just in a different way than I did Smurf. The CP3 can't supply the fuel rail when it isn't getting enough fuel at the inlet supplied by the lift pump. Yes I deffinately reccomend getting a fuel pressure gauge to find out. But I would be willing to bet the farm that your lift pump is not keeping up with the demands of the CP3 injection pump. And not your CP3 getting all the fuel it needs and not being able to keep up with the demands of the engine.

PapaSmurf

Time out there buddy. I'm not sure who Smurf is I am the one that wrote the above post PapaSmurf. I already stated that I was not trying to start anything. The statement was made that that the CP3 don't have fuel supply problems until 600 HP or something to that effect. I just said I didn't agree, I did not try to turn your words around. I said we have a fuel supply problem (Fuel supply to the CP3) on a truck that is only 500 HP. I do not understand your last sentence. PM me and please explain.
No harm was intended.
I have been dealing with diesel engines for roughly 30 years now. I don't know who you are or your experience level, you maybe a sixteen year old kid or you maybe be a Master Tech ASE cert. Diesel Mechanic. My suggestion is not to be so senstive.
Hope you feel better
See Ya
Chris

PapaSmurf

hoehand
Just to throw out another item to you.

I am not trying to insault you,but I want to let you know my thought process on this.

Bear with me for a minute.
The CP3 is basicaly a high pressure pump.
As long as the CP3 is supplied with a STEADY SUPPLY OF FUEL regardless of the engine RPM it is fine. Normally problems don't start until folks add fueling boxes and such, then the injectors deliver more fuel to EACH cylinder which puts more of a demand on the CP3 pump which in turn wants more fuel from the Lift pump or low pressure supply pump. The supply(lift) pump is a low (About 8 psi on our 2004 3500) pressure pump and the CP3 is a very high pressure pump ( I do not know the exact pressure but it is in the area of 20-40,000 psi) On our 3500 on aggressive setting it will drain the rail pretty fast (1/8 of a mile)

It is very hard to help you figure out what is going on in your truck unless you have gauges. I recommend the following gauges at a min. EGT (most important), Fuel pressure, and Boost. Do you pull or haul very much weight? If so you may want to turn the box down when you do.

I have a strong running 2001 2nd gen truck that on the dyno has 429/927 that is a six speed with a South Bend Clutch Con O Fe. When I pull our 5er or our gooseneck loaded or unloaded I leave the TST box off and just pull with the upgraded injectors and other stuff.

I am not sitting in the truck with you but after I reread your first post in this thread. My truck is laggy if I get into it at low boost.
This is a bad habit of mine lately, I get in front of a car in the fast lane of a four lane road and get off the boost and then mat the go pedal and pour out massive amounts of smoke from my 2001 6 speed all over there car. It just lets them know that the passing lane is for passing and not for cruising down the road. I would not recommend doing this, I am sure I will be pulled over by the police sooner or later and I will have to tell them that my old truck has been acting up lately and that it might be caused from the new diesel fuel.

Just trying to help
See Ya
Chris

TAS05CTD610

I figured this was going to be something about siphoning the fuel outa the rail with a hose and getting a mouth full of it

Most people here are right. If your running boxes, towing heavy, doing anything get gauges. asking a question if the rail is being run dry is a good question but most will ask what the gauge is reading, and there not that expensive. 100 bucks for a complete kit is much much cheaper than if you do lean it out too much.

I have EGT, Boost, Fuel, and Tranny. I mean the new autos will shift down to cool them off, so is it needed??? Problably not but better safe than sorry. And yes I like my truck having more gauges than a 747

Billy Ram

I believe the cp3 will only flow what its displacment is. Rpm and fuel flow restrictions will have a effect. High flow needs to have pressure at the inlet. the more the better to a point.
Too much duration can drop the rail pressure especially at lower rpm. This causes poor atomization. Adding pressure and turning back the duration seems to make a better tq. curve. I have looked at a lot of dyno graphs and you can see where the rail pressure drops. When pressure drops tq. numbers drop.
The older non cr 24vs controlled pressure with spring tension in the injectors and it gives you more low rpm tq.
When we have a pump with more volume we will see better #s

hoehand

Gauges and an upgraded fuel system are already in the works. The only reason I am doing this a little out of order, is due to good deals showing up.

I am getting the muffled "popping sound at full throttle when I accellerate rapidly. Maybe my turbo is fluttering? Also, this stack smokes heavily. Sometimes it has a hard time cleaning it up at all. It is a very strong stack, but I think it is going to take a little tuning. I think there is something else going on here though.

I will have to wait until Quad's monitor is ready, and I my fuel supply issue is taken care of before I can really start looking.

no_6_oh_no

The popping and black smoke generally indicates the rail pressure is low for what is being demanded. Either The CP3 can't keep up with the demand or the rail pressure relief is popping early. Might want to consider a rail pressure gauge unless the Quad monitor has that function.