What injectors do you run?

thechoochlyman said:
Where the nozzles with fewer but larger orifices have their big advantage is in high boost applications. The larger droplet size translates to greater fuel jet penetration which means more power on the top end. The smaller orifice version will have jet penetration hindered by opposition from the high boost pressure and the power will fall off when this happens.
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You do realize you just quoted something I wrote correct?

thechoochlyman said:
The representative of a diesel performance shop. Since he doesn't currently offer any 7 hole injectors for a 1st gen, I can understand why he's pushing the 5 hole injectors so strongly.
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We actually do offer the 7x0.010" nozzle with the 148* cone angle, and again we mainly use it for the 1st Gen crowd.
 
CosmicDP said:
For anybody interested in learning more about the real science behind this, you should find this article interesting and informative. Don't worry about all the math in the middle, just read the discussions at the beginning and the end to get the main points. The jist of the article is that gas kinetic modelling shows that in a dynamic environment the smaller fuel droplets still burn more completely than the larger ones showing dynamics does not alter the basic chemistry of the combustion of liquid droplets. This results in less soot production and this is the reason that in general, injector manufacturers are tending in the direction of fuel injectors with a larger number of smaller orifices. The increased atomization leads to more thorough combustion and therefore decreased emissions.

Disclaimer: This is not intented to prove a 7 hole injector is always superior to a 5 hole injector, they're not. It is just simply to point out that real science shows 7 hole injectors have a certain set of advantages over similarly flowing 5 hole injectors making them the better choice for certain applications.
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Thanks for your posts, CosmicDP. This was the exact type of thing I'm looking for. It's a totally different thing to build something and know how it works only by building/testing, and to know how it works based upon scientific and chemical properties.
 
Smokem said:
You do realize you just quoted something I wrote correct?

We actually do offer the 7x0.010" nozzle with the 148* cone angle, and again we mainly use it for the 1st Gen crowd.
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A. Really? You didn't really seem to be agreeing with what I was saying along those lines before.

B. So where do you sell them? I'm still interested in those injectors (are 148* injectors SAC? That's what I've heard I'll be wanting to use), can you tell me where you market them so I can check them out?
 
That was a quote from the 7-hole thread on Cummins Forum, yes I recognize when people take what I say and try and educate me with it.

We sell them, they are on our Classic Line price sheet, but not on the website at this time.
 
thechoochlyman said:
Thanks for your posts, CosmicDP. This was the exact type of thing I'm looking for. It's a totally different thing to build something and know how it works only by building/testing, and to know how it works based upon scientific and chemical properties.
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Anyone can Google sac nozzle and read until they think they are an expert, but real world results in different applications is what I use for comparisons. I have talked to the people @ Oxford Lasers a good bit, so tell me what I am missing?
 
The real reason I would push against them is that I don't want people to have to spend their money twice, nor do we want to build something that the customer won't be happy with the first time. We have seen a large influx of people wanting to go back to a 5-hole nozzle lately, even one gentleman that has tried both 7-hole nozzles.

Now if you really want to try them, I would suggest looking into using the Cummins nozzle that is micro-blind and 145* cone angle, as I feel like they are a better fit than the JD nozzle.
 
thechoochlyman said:
Thanks for your posts, CosmicDP. This was the exact type of thing I'm looking for. It's a totally different thing to build something and know how it works only by building/testing, and to know how it works based upon scientific and chemical properties.
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Smokem said:
Anyone can Google sac nozzle and read until they think they are an expert, but real world results in different applications is what I use for comparisons. I have talked to the people @ Oxford Lasers a good bit, so tell me what I am missing?
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Weston stoled my thunder a little here. Anybody can read until they are blue in the face then come on the boards and regurgitate their findings. Bottom line is, some of us read and some of us "do". It's great to know and do research on what your getting into but it would also be wise to listen to the people that have been there and done that as well.
 
This whole thread is full of trolls from that CF reject site named after a chick flick.
Why don't yall travel your happy asses back to your place before I make the trip permanent...mmmkay?

I wouldn't waste another thought on these idiots.
 
UNBROKEN said:
This whole thread is full of trolls from that CF reject site named after a chick flick.
Why don't yall travel your happy asses back to your place before I make the trip permanent...mmmkay?

I wouldn't waste another thought on these idiots.
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:clap: Rich, you have been on fire the last couple days! :hehe:
 
attention-fail-science.jpg
 
Smokem said:
Actually, no they don't. I appreciate the fact that you found a few Tech Documents on the internet, but again, there are variables these documents do not account for. Piston bowl design, cylinder pressure, injection pressure, and cone angle are the things you are missing in this equation. All of these being equal, a nozzle with a higher orifice count and smaller orifice diameter can be more efficient, but not in every instance.
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Actually, yes they do. You just seem to have missed the main point of my post. I agree with everything you say here, but that does not reflect how the conversation began. This began with you stating that the OP's original comment about the relationship between orifice size, atomization and efficiency of combustion reflected advertising hype and not fact. I simply pointed out that this is not true and those Tech Documents that I somehow fortuitously stumbled upon on the internet are called references. When a person makes a statement of fact, it should be backed up with verifiable references so that people can differentiate between opinion and fact. That is what I did. Clearly you did not read those articles because they in fact address some of the issues you just pointed out and more so you could have appealed to them to back up your points.

All those other factors you point out go into determining the overall efficiency of an injector in a specific application. They do not however change the underlying fact that an injector with a larger number of smaller orifices will produce smaller fuel droplets and that a smaller fuel droplet will burn more rapidly and completely than a larger droplet. That was what you seemed to be calling advertising hype and that was the one and only point I was trying to address in my reply to you. What these other things you list do bring into the discussion is factors that determine things like jet penetration and air fuel mixing. Those significantly affect what percentage of the total fuel will combust and therefore are key factors in injector selection. They do not alter the fact that a smaller droplet will burn more rapidly than a larger droplet. Instead they determine how many of the smaller droplets will begin to burn in the first place. The ideal injector, and I'm sure you would agree, will find the optimum balance between atomization, jet penetration, and mixing for the specific application.

You need to optimize dispersal and mixing but you also need to optimize the droplet surface reaction rate. In a turbocharged application with higher boost levels this, as you well realize, sets a 5 hole injector against a 7 hole injector. The former optimizes dispersal and also mixing while the latter optimizes droplet surface reaction rate. The trick, again as you know, is to find the specific design that gives the best combination of both for a given application. On the part of the injector purchaser it comes down to compromises. Each injector option has its inherent strengths and weaknesses and it is up to each individual to determine which weaknesses they can overlook to obtain which strengths.


Smokem said:
I can agree that in certain applications a 7-hole nozzle would be more efficient, and I have. Cummins actually used a 7-hole micro-blind nozzle later in production. My disagreement is with the large sac John Deere nozzle, I feel it is best suited for a lower injection pressure setup such as the VE.
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I do not disagree with you on this point either. I was merely trying to focus the post on one point and on that point only, the relationship between orifice size and atomization and how that droplet size affects the combustion properties of the droplet. Maybe I should have explicitly stated the all other factors being equal part, but I assumed it was understood by all.
 
CosmicDP said:
This began with you stating that the OP's original comment about the relationship between orifice size, atomization and efficiency of combustion reflected advertising hype and not fact. I simply pointed out that this is not true and those Tech Documents that I somehow fortuitously stumbled upon on the internet are called references. When a person makes a statement of fact, it should be backed up with verifiable references so that people can differentiate between opinion and fact. That is what I did. Clearly you did not read those articles because they in fact address some of the issues you just pointed out and more so you could have appealed to them to back up your points.
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Have you watched the atomization of a 5-hole nozzle vs a 7-hole nozzle during testing in person? What I mean by this is the actual throttling of the needle on the seat. The discharge rate of a different nozzle design effects this far more than the hole count.
 
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CosmicDP, you do realize that there is much more to an injector than orifice size and hole count right?
 
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