Bosch Motorsport nozzles bashing thread

It describes the air tumbling primarily setup from the ratio of bowl height vs width and the squish volume around the crown.

This is seen early during mixing and SOC or start of combustion.

The common bowl today is kind of a variant of both.
Both the 6.7 Cummins and Scorpion use a chamfered re-entry bowl. The chamfer actually sets up spray split towards the squish flow.
 
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There is some good, and not so good, Info in this thread. But the basis of this thread is to say the motorsport nozzle will not work and will cause damage to the late(non reintrant) bowl. This could not be further from the truth. I can see why it got so far on CF because thats what always happens over there. But I cant believe it here.

I have probably 20-30 sets of these of all sizes in the field as we speak, including in everything I own. I have three trucks. Each one has a different bowl design, reintrant, non reintrant, and a custom bowl that we designed. All three engines are running motorsport nozzles. Two are 100hp, and one is 200% over. I have put about 50k miles on the non reintrant at 600+ hp towing 18k, about 20k miles on the reintrant. We have about 150 passes on the custom bowl at 1200-1300 hp, and about 40 passes at 1400+hp. Out of the 20-30 sets I have in the field, along with my three, guess how many piston failures? ZERO. I am pretty confident that we have one of the two biggest hp CR's in drag racing, and never have had a piston failure. Torrey(the other one of the two mentioned) has not had any either with this nozzle as far as I know. We can go over theories all day, but Im telling what works in real world applocations. So all the guys that are freaked out about the guy on CF melting down with motorsport nozzles, get over it. Its another melted late 5.9. There were thousands before that one and will be thousands after. IT HAS NOTHING TO DO WITH HIS NOZZLE. If the motorsport nozzle was the cause of the damage, dont you think we would have seen a failure by now? And as far as power, they are great. If someone thinks there is a better option for power, I challenge you to prove it. There will be people say that something else will make more power, but I bet you no one sends a set to compare.
 
Blacksdieselhp said:
There is some good, and not so good, Info in this thread. But the basis of this thread is to say the motorsport nozzle will not work and will cause damage to the late(non reintrant) bowl. This could not be further from the truth. I can see why it got so far on CF because thats what always happens over there. But I cant believe it here.

I have probably 20-30 sets of these of all sizes in the field as we speak, including in everything I own. I have three trucks. Each one has a different bowl design, reintrant, non reintrant, and a custom bowl that we designed. All three engines are running motorsport nozzles. Two are 100hp, and one is 200% over. I have put about 50k miles on the non reintrant at 600+ hp towing 18k, about 20k miles on the reintrant. We have about 150 passes on the custom bowl at 1200-1300 hp, and about 40 passes at 1400+hp. Out of the 20-30 sets I have in the field, along with my three, guess how many piston failures? ZERO. I am pretty confident that we have one of the two biggest hp CR's in drag racing, and never have had a piston failure. Torrey(the other one of the two mentioned) has not had any either with this nozzle as far as I know. We can go over theories all day, but Im telling what works in real world applocations. So all the guys that are freaked out about the guy on CF melting down with motorsport nozzles, get over it. Its another melted late 5.9. There were thousands before that one and will be thousands after. IT HAS NOTHING TO DO WITH HIS NOZZLE. If the motorsport nozzle was the cause of the damage, dont you think we would have seen a failure by now? And as far as power, they are great. If someone thinks there is a better option for power, I challenge you to prove it. There will be people say that something else will make more power, but I bet you no one sends a set to compare.
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:clap:
 
Smokem said:
Let's look at this in a simple way, both the Duramax and 325hp Cummins have pilot injection, see the following;

Cummins - 124° angle 76mm bowl
Duramax - 158° angle 64mm bowl

Why is everyone so worried about spraying out of the bowl on the Cummins engine but not on the Duramax engine? People seem to be missing the obvious here.
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IMO because we have no set timing mark, just a level of more or less timing. I am not sure if you set timing to an actual degrees with EFI Live, but either way the 03-05s arent able to get it anyway.
 
mikmaze said:
speed, UDC timing values are actual timing numbers, not + or - from where you are/ were.
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That pretty much impossible. In a gas application you fire a spark plug and you know when the thing lights off. With a diesel all you can control is the starting point or ending point of injection. By moving those around combustion is going to move. I can very easy change when the burn occurs by putting more or less fuel in and then if you have pilot injection it changes again. That is the main reason the INDUSTRY STANDARD for diesel is using Start of Injection to locate what is going on.
 
but in context, the question was do you just pick a random value like in s06 or ssr, , or an actual timing number........ I stand by my statement.
 
mikmaze said:
but in context, the question was do you just pick a random value like in s06 or ssr, , or an actual timing number........ I stand by my statement.
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Understanding what is really going on is important I believe as many just read the internet and take it as the bible. As for tuning or just pushing the button on a programmer that you have no idea what is really happening I would have to agree with you.
 
Diesel Tech said:
Understanding what is really going on is important I believe as many just read the internet and take it as the bible. As for tuning or just pushing the button on a programmer that you have no idea what is really happening I would have to agree with you.
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Can you get on topic or just zip it? Your a constant derail...first about the word timing vs start middle of end of injection and now about tuning. The post is about spray angle.
 
Understanding what is really going on is important I believe as many just read the internet and take it as the bible.
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That's true. BUT, I don't know of anyone on CompD who runs a crank shaft encoder and in-cylinder pressure transducer...so what metric are you suggesting for measuring start of combustion, mass fraction burned, heat release, etc, etc? It's undisputed that that info is what's needed...but if you don't have the right feedback, tuning by those parameters is guess work.

I just checked the SAE library, and it looks like there are at least a dozen papers concerning spray angle and orifice shape effects on fuel atomization and combustion. I don't have time to read them now, but the "scientific" info is there if someone is truly interested.

It would be most helpful if someone with an engineering background would take the time to read the available literature, and then couple that with what's going on in the diesel performance arena. To me, there's always been a disconnect between to two. Many brilliant minds in the performance arena are making great power...mostly by trial/error and real-life experience. There's many brilliant minds in engine R&D in the OEM world, and there's no doubt much that could be learned and gained from their expertise...but their emphasis is not solely on performance. Join the knowledge of these two together, and we'd all benefit.

If you're willing (and able), jump in, do some leg-work, and be that middle-man.

--Eric
 
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cquestad said:
Can you get on topic or just zip it? Your a constant derail...first about the word timing vs start middle of end of injection and now about tuning. The post is about spray angle.
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If you do not do the two together then you are never going to get it. When you start changing spray angles and hole sizes you must also change SOI,pilot injection points and quantity to get them to work together properly. I thought that this is what this thread was about. Understanding how it really works.
 
ENafziger said:
Join the knowledge of these two together, and we'd all benefit.
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I agree with your general point, but I disagree with the selected statement. There are people working on ideas that uses much of what has been learned first hand and by accumulated data on the OEM side. Now if these point us in a better direction, don't be surprised if the mainstream doesn't hear about it for a good while if at all.
 
There are people working on ideas that uses much of what has been learned first hand and by accumulated data on the OEM side. Now if these point us in a better direction, don't be surprised if the mainstream doesn't hear about it for a good while if at all.
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Yes. Maybe I could've worded it better. Maybe I'm not in the right loop, and the two aren't as disconnected as I think. Nevertheless, I don't see much of that here (although there is more than on other sites). Possibly those who do know more, either don't want to divulge what they know or choose not to.
 
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