Let me ask it a different way

[cougar]

What I would, and I think others as well would like to know the advantages and disadvantages of 4, 5, 6, 7, etc hole injectors. Not everyone sees "performance" as the drag strip or dyno, so keep that in mind also. Me, I'm looking for a hard working heavy hauling set up. What I have is okay, but it has its disadvantages and I would like better.

[JustinRhodes]

I aswell would like to know. i like my 5 hole injectors so far, but i have only had them in since yesterday

[Kasper Cummins]

I like my 5X13 because they burn clean, make good power, and I got better mpg.

[cmann250]

I would think that an injector that has the same cross sectional area with more holes ( smaller holes, but more of them) would be more efficient than another injector because it would atomize fuel better and therefore smoke less and get better mpg's

[oldestof11]

Cmann got it.

A 7x10 should be cleaner than a 5x14 or a 6x12. Now, depending on who builds it and your other mods (timing, AFC, etc), it can go either way.

I remember that Bosch 190's are a smaller injector than even the intercooled nozzles but burned cleaner and you got a mileage bump.

[cougar]

I would think that an injector that has the same cross sectional area with more holes ( smaller holes, but more of them) would be more efficient than another injector because it would atomize fuel better and therefore smoke less and get better mpg's

Those were my thoughts as well, performing better in the lower RPM range also. Yet I've had others say it makes no difference to fewer bigger holes is better. And that is why I've asked the question. The "I like" answer doesn't answer the question. Lets see some cold, hard science.

[delinquent]

I think If you can put of with the "dirty" the 4 hole or 5 hole will be the most pwerful.

[ahale2772]

Gotta keep in mind this discussion needs to note what injectors for what injection pump, P-pumps are proven to like 5 holers, vp44 trucks like small nozzels and high preszure to maximize the spray pattern/ runner flow of a 24v head. Im gona take stab and say VE's are very sensitive to pop pressure. Im gona go with 5 hole nozzles when i fork out the cash just because so much power has been made with them in the p-pump relm, the air flow of the cylinder head into the piston bowl has as much of an effect on how they burn as anything, and a p-pump head is as close as a ve head as it gets, cant really compare it too 24v stuff. Ive yet to see a good reason why 6 hole nozzles work great on a VE, they clearly do, but the question is why?

[cougar]

Lets keep the discussion to VE pumps with stock rotor heads.
Also in this discussion "power" is a relative term that you need to define, aka in relation to what.
What I am trying to establish in this conversation is an effective comparison of injectors with similar cross sectional areas, but with a different number of holes and hole size.
What combination would be best for towing vs daily driving vs racing/dyno.
HP/TQ
Fuel economy
EGTs

[oldestof11]

I will see if Weston will get back on here to answer. He would know more than anyone.

Another thought though, what is the turbo? A quick spooling, appropriately sized turbo can take more injector than a stock or large A/R housing on the exhaust...

[dpuckett]

I seem to remember KTA saying the VE trucks like the 4-6 hole tips, something about thermodynamics and swirling in the piston bowl, or something like that. He didn't go into great detail. I have had less than stellar experiences with 8 holers in a nonIC truck.

[Tacoclaw]

Lets keep the discussion to VE pumps with stock rotor heads.

I disagree. The P-pump resides within the same engine layout as our pump. It's capable of both higher injection pressures, and more fuel throughout the RPM range.

It stands to reason that our pumps would then like just a little different of a setup, injection-wise. Bigger holes and less of them comes to mind with our pump's shortcomings, in an all-out horsepower setup, anyways.

You can start substituting more holes for hole size, to try to get atomization up, but you'll actually have to get your cross section higher to get the same amount of fuel through it. There will be a point of diminishing return on the number of holes, especially with our lower pop pressures.

IMHO of course.

[ahale2772]

I was just noting that lots of the 7 and 8 hole info out there is tested on 24V trucks, apples and oranges when its comes to head flow VS a 12v

[Begle1]

There's a lot more to holes than the number of holes. There's the shape of the holes, the angle of the holes, the position of the holes...

The "little holes atomize better" thing is intuitive, but has been proven wrong, or at least inaccurate as it pertains to Diesel injectors. Little streams of fuel at injection pressure differentials aren't strong enough to carry very far into the cylinder; the little streams smack the air in the cylinder and diffuse out too soon. Fewer bigger holes throw a bigger slug that makes it farther into the cylinder before they fully diffuse.

At least that's one explanation that explains why 4-6 hole injectors tend to outperform injectors with the same cross section and more holes. The important part isn't the explanation, it's the evidence.

And at any rate, there's a lot more to injector design than just hole number and size. Talk to an injector person and trust their experience and intuition.

[KTA]

This question can not be answered. Cummins has like a hundered diffrent part number injectors for the 5.9. The dynamics of cylinder combustion make it virtualy impossible to model even with todays computers. Therefore the method still employed by the engine manufacturers on mechanical pump motors is to test various injectors until the one with the best performance (power, smoke, emissions) is found for a given application. You might have 200 engines rated at 200hp, but one is at 1800rpm and the other 2500rpm. The ideal nozzle will be diffrent for both engines. Then you get into what type of engine is it and what sorts of loads and conditions does it run at. A constant speed genset will use a diffrent nozzle from an automotive engine rated at the same power because of diffrent running conditions.