bully dog injectors

[denverdale]

Saw a TV show this last weekend and they were advertising new injectors for the Duramax from Bully Dog. Sez hope HP and Torque as well as better mileage. Has anyone tried them? Sounded interesting to me.

Denver Dale

[Heartbeat Hauler]

I saw that show,I think it was Horsepower TV(Spike channel). Seems like you would need more than just injectors for the horsepower increase. I can see where bigger injectors would have more potential, but without more fuel pressure or computer calibrations (more pulse width I think is the term)the injectors would just spray the same amount of fuel. I'm not sure I understand all that well how the injector would increase HP by itself.
JP

[a64pilot]

Heartbeat,
If pressure and duration (pulse width) are the same then a bigger orifice would flow more fuel. Kinda like putting bigger jets into a carburator

[CntrlCalDmax]

After that show I searched the internet but came up with nothing. I would like to know more if anyone has information. I just called Bully Dog and could only get voice mail.

[Kennedy]

I'm not sure how far things have progressed (outside of my sources) but I've taken a step back in abscence of new nozzle assemblies due to a VERY large variance in the condition of the cores that I have seen.

I'll be having a set analyzed soon as the result varied a bit much for my liking. Aside from that, the only way I'm going to do them (and I hope to have a set in yet this month) is with NEW injectors...

[LanduytG]

To the best of my knoledge new nozzles are not avaiable yet. These guys are just running exsisting nozzle through an EDM machine or extrude honing them which IMHO is just is worse than using the EDM.

New nozles will be available very soon that will be matched for flow right out of the factory. This type of nozzle has been used in other applications with great results and the price will be well within reason too. They will be available in stock size and at least one my be over size. The over size will spray a cone shape stream instead of a straight stream like they do now. This will allow the fuel to atomize better so you will get better burn. Which means better power less smoke and more economy. On the economy side it will be totally dependent upon your right foot.

Greg

[Heartbeat Hauler]

a64pilot,
I get it, I guess there is not enough difference in orifice size to effect the amount of pressure.
Thanks, sometimes you get a brain cramp and stuff just doesn't make sense.
JP

[Amianthus]

There are several factors involved with fuel delivery at the injector level when it comes to performance. All of which are intimately related. Some of them have been refered to by Kennedy and Greg.

When injecting fuel you need to consider pressure, spray angle, atomization, flow rate.

We all want more flow, and there are several ways to get it. But with each way there are pitfalls.

One popular way is extrude honing. An abrasive solution is pumped through the tips. It polishes and expands the fuel passages in the tip allowing for more efficient flow to the tip. The downside is that too much will cause the atomization to suffer (resulting in more smoke and loss of performance) and it can also damage the seats in the tips. It also changes the spray angles so that the fuel is not delivered in the combustion bowl.

Another way is EDM. This allows for more precise control of the tip oriface size and spray angle. But, as was mentioned above, you can make the holes too big and cause poor atomization of the fuel. If you keep the hole size the same, and just add more holes to increase flow, you can weaken the tip and cause it to fail.

One final way (that I know of) are custom tips that are designed with multiple holes and custom geometry. These processes are kept in pretty tight confidence as it is what a lot of competition drivers use and they don't want those secrets to get out. I think you'll understand.

There may be other ways to manipulate tip design and manufacture that I am unaware of. But the two described above are the more popular practices in use right now. As for what Bullydog is doing, I don't know. But I would venture a guess that they are extrude honing them.

I hope that helps.

[mackin]

One popular way is extrude honing. An abrasive solution is pumped through the tips.Is this not the same as OE 5/10 um filtering (abrasive fluid) for 20K then 2 um for 10K (polish) ???

Dunno bought you but that's what I'm did ,done ..... Ok ok so there not balanced ,can't have everything ..... But I got more fuel ....

Mac http://www.turbodieselregister.com/ubb/hihi.gif http://www.turbodieselregister.com/ubb/hihi.gif http://www.turbodieselregister.com/ubb/hihi.gif

[Kennedy]

Done properly, and in MODERATION, extrude honing can add flow w/o excessive oversizing of the spray holes by acting muckh like porting or a multi angle valve job.

From what I am told, the Dmax nozzles take at least 3x longer to extrude than the PSD, and those are said to be WICKED hard. The problem I suspect is the pintle OD is wearing out allowing excessive bypass. Time will tell...

[Amianthus]

I tend to agree. It's no different than the honing of a Cummins injector. A little bit is good. Too much destroys the seats in the injector and you wind up with fuel dribble at the tip and in some cases, excessive bypass and leakage. It should be no different with a Dmax injector, in that honing can compromise the pintle if not done properly.

From what I understand, the split-shot design of the HEUI injectors on a Ford is what makes honing difficult. I can't imagine that a Dmax injector would be tougher than that. Although I could be wrong.

[LanduytG]

The Dmax is a standard p150 Bosch nozzle with a 7 hole pattern nothing really special. Honing you have no control and it will not act equally on all the holes in the nozzle. As soon as a friend of mine gets back from Italy we might have some new Dmax nozzles to try. At the most only a few weeks before we have them.

Greg