Since i have just upgraded my fuel system with a holley blue lift pump and happy i don have to worry about fuel pressure it stays about 15 psi now it time for injectors i was thinking about 50 or 60 hp the truck has 112,000 miles on it now if i buy nozzles do they check my old injectors to insure they are in good working order and who would be a good place to order from.  I have heard they some companies injectors will smoke more than others with that being said what do yall think about ddp or who would compare to them. They advertaise that even there 75 hp injectors wont smoke more than stock i find this hard to believe. Wanted just enough to be happy with, without hurting my mileage thanks for your input  

With 112,000 miles on your injector pump I would be concerned about it more than I would the injectors.

You should be able to get away with just nozzles since you're not having issues with the injectors.

Get your IP looked at first before you do anything as it'll be the most expensive part to replace.




Kris  

112k isn't that bad. Unless you 've had serious FP problems in the past I wouldn't worry about it. I'd bet a good chunk of money that there are many more 24v trucks out there with many many more miles than you have with no IP problems. The Ip gets a lot of flak on these trucks because it is one of the few things on these engines that has a tendency to fail. However I think the problem looks worse than it actually is because people who have problems get on these forums looking for help. Those who have no problems we never hear from.

 Yes you can buy nozzles and if you have them installed by a good shop they will pop test and leak check your injectors. You can have them remove the injectors and install the nozzles or you can remove the injectors yourself. Some people have went ahead and installed the nozzles themselves without checking the injectors. At 112K i would have them checked just in case. In all actuallity the mileage isn't all that high. Mine was just over 100k when mine were installed and the injectors were fine. But poo happens

However with an edge comp I don't really know how much you'd gain for HP on a stock turbo. A set of 100 horse injectors will smoke if you try but are very drivable and will get good mileage. But you will have to turn the comp down to keep from getting too hot.  

The IP has a tendancy to fail when you upgrade the injectors and not the rest of the fuel system.  The bad part is most folks don't understand this.

With a good IP and LP/FP, running 50 to 60hp injector tips you're still in a safe range but once you get near triple digit increase in horsepower you're putting too much stress on the rest of the stock fueling system and are increasing your chances for an expensive failure.  Most VP44 replacements are in the 1200 to 2000 dollar range.

With tips I'd say get a hotrod VP44 since it's ready to go for your needs, and then replace the FP/LP with one from FASS, AirDog, etc., to make sure your new IP gets enough fuel.

Remember, the VP44 needs fuel to use it for cooling.  The added benefit is keeping pressure high to maximize fuel atomization, which will really be needed with those bigger tips.



Kris  

The IP has a tendancy to fail when you upgrade the injectors and not the rest of the fuel system.  The bad part is most folks don't understand this.
With a good IP and LP/FP, running 50 to 60hp injector tips you're still in a safe range but once you get near triple digit increase in horsepower you're putting too much stress on the rest of the stock fueling system and are increasing your chances for an expensive failure.  Most VP44 replacements are in the 1200 to 2000 dollar range

Guess you missed the part where he said he upgraded his lift pump huh?

With tips I'd say get a hotrod VP44 since it's ready to go for your needs, and then replace the FP/LP with one from FASS, AirDog, etc., to make sure your new IP gets enough fuel.

The vp on his truck will last him to over 500 hp. Why go with a HR? If his ip decided to die on him maybe... but he is pushing a bit of fuel the way it is. I don't know that a HRvp would benefit him that much.  

Why go with the HR VP44?

My understanding is that the VP44 was used until a common rail design could be had since newer emissions standards were coming out that had to be met.  This means that the VP44, by its very nature, was designed to use less fuel.

Since he's going to use bigger tips on his injectors, he's going to need extra pressure to ensure fuel atomization and the HR is rated for a 100hp increase.  If the fuel isn't atomized properly you end up with unburned fuel and lots of black smoke, which increases EGT's.

And yes I missed his line about replacing the FP/LP, but let's not nit-pick about it, shall we?



Kris  

thanks you guys i'm happy with my holley blue it seems to do just fine nearly went with a fass til i remembered this was out in the garage it didnt hurt to try. I think i will go with dynomite diesel nozzles about 50 to 60 hp i think i will be safest they i kind of a lead foot sometimes even when i dont need to be and be happy for a little while i have picked out my turbo its the htt 62/71/13ss from everybody that i have talked to and other people that went with the 64 i believe its just right for my thanks again guys  

Nice turbo choice. I've only heard good things about those. Hopefully I have a guy talked out of a 62/71/14 which will flow similiar to that one.

My personal experience with my 100 hp sticks is pretty good. With no chip the max egt I have ever seen is 1000 which is nothing for these trucks. with the EZ i came close to 1200 and then it cooled off. With my quad though I see about 1600-1700 if I turn it up, which I don't do often for obvious reasons.

Even with a stock turbo 100 sticks will cause you no problems. Maybe if you tow heavy and are in the montains. But I don't know if you do or not. with the HTT it should be even better. But the decision is up to you and I can only relate my experiences with my own rig.

Marine, I understand where your coming from however I think there are a few things you misunderstand. 1 injection pressure is control by the injectors not the Injection Pump. Sure the pump creates the pressure however the injectors are calibrated to inject (or "pop off") at the pressure they are set at. Which is in the 3000-3400 PSI range. The stock pump, if allowed to, will produce more than that. But that would probably have an effect in longevity. One of the problems with the HRVP is how new they are and if they have any long term reliability issues. Also the increase amount of fuel that the injectors will flow won't affect the pressure all that much. I run 100 hp injectors and my stock HO pump and on a recent trip to the western slopes of the rockies and back I got 19 MPG running 70 in a truck with 4.10 gears and 33" tires.  

I pulled this info from a couple of websites that have some of technical data available on the VP 44 .....

The fuel injection pump (VP44) is an electronic rotary distributor pump. The pump performs four basic functions:

- Producing the high fuel pressure required for injection
- Metering the exact amount of fuel for each injection cycle
- Distributing the high-pressure, metered fuel to each cylinder at the precise time
- Varying the timing relative to engine speed.

A cam ring with three plungers, a rotor, and an electronically controlled fueling solenoid valve is used to develop and distribute the high pressure required for injection.

A worn or damaged internal transfer pump, plunger, or fueling valve can affect the pressure and the amount of fuel injected, thus reducing the power from the engine. Generally, if the fuel-injection pump is injecting fuel from one outlet, it will deliver from all outlets.



I think your statement about injectors controlling pressure is slightly off, so lets discuss it.  Since the injector pump is what creates the pressure, the injectors are simply responding to it by either popping at the right pressure or waiting until that pressure is reached.  In reality they aren't controlling the pressure but just responding to it, or the lack thereof.  Without enough pressure they either won't pop, or if they do pop after making minimal pressure the other concern now is proper atomization.  Without enough pressure, the fuel won't be atomized properly and your fuel won't burn right.

This also is where my initial concern about his stock VP44 comes into play.  If you read the last paragraph of the quote this is why I'm saying that looking at his stock VP44 or a HR shouldn't be dismissed.  Running bigger tips does put some extra stress on the IP so it does need to be looked at carefully.


Kris  

Thats true the injectors are responding to the pressure created by the IP. However if the IP creates enough force to retract the plunger in the injector then proper atomization will happen.

Say the injector pops off at 3000PSI(I'm just pulling it out of the air). The pressure in the injector and lines in that moment is 3000 Psi all the way back to the plunger in the pump. When the plunger in the injector is pushed up by the pressure of the fuel it is under 3000 PSI. It gets injected at that pressure.

 Atomization at that point is determined 1 by the pressure its under and 2 by the fine holes that are in the injector tip. If the pump is weak and cannot inject as much fuel as it needs too the injector plunger will seat again and the fuel injection will cease. Yes the cylinder will not recieve as much fuel but the atomization of the fuel that made it into the cylinder will but unchanged or only slightly less than Ideal but will not be dramatically affected. Power, however will go down. If the IP cannot make 3000 PSI then no fuel is injected.

Think of it this way. A releif vlave is considered to be a controling device is it not? It keeps the pressure in a system below a certain level. If the pressure gets too high what happens? The relief valve "pops" off until the pressure in the system is below a certain level again. So you could say it's "controling" the pressure in a system correct?
 Injectors on the 24 and 12v trucks operate the same way. When the pressure in the lines overcomes the tension of the spring in the injector body they act the same way as a relief valve by allowing fuel out at 3000 psi until the pressure in the line drops below that and the spring can force the injector shut again.

 Bigger injectors will flow more fuel by slightly increasing their size. Just like a bigger relief valve will be able to release more pressure in a circuit faster. However they should inject at near the same pressure. Remember pumps just create flow. Restriction creates pressure. The more pressure thats on a circuit the harder it is on a pump.