Bosch Motorsport nozzles bashing thread

dickshaker said:
^^^ LOL typical dtr unicorn truck and operator.
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You clearly have no knowledge of me. STFU

There is nothing unicorn about it. You more than welcome to witness anything yourself...or talk to the many that can personally vouch.


Lets get back on topic..yes?

So...if the idea behind narrow spray angle in wide bowls was to promote cleaner burn...ie less emissions for the 4.5-07 pistons...and switching to wide spray angle in the wide bowl produces more power (even if it is a short term solution), what happens then you fire the same pulse width, pressure, and optimized timing at a piston bowl that was designed for a wide spray pattern?

Less power?
 
cquestad said:
You clearly have no knowledge of me. STFU

There is nothing unicorn about it. You more than welcome to witness anything yourself...or talk to the many that can personally vouch.


Lets get back on topic..yes?

So...if the idea behind narrow spray angle in wide bowls was to promote cleaner burn...ie less emissions for the 4.5-07 pistons...and switching to wide spray angle in the wide bowl produces more power (even if it is a short term solution), what happens then you fire the same pulse width, pressure, and optimized timing at a piston bowl that was designed for a wide spray pattern?

Less power?
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Why you asking us? You're the one that said Cummins knows best, ask them.
 
LReiff said:
Why you asking us? You're the one that said Cummins knows best, ask them.
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Should i be disappointed or not surprised you offered nothing more than another sarcastic remark?

Bless us with some knowledge or at least logic.
 
My question is why with the narrow spray angle on a wide bowl does it seem that most melt downs are on the outer edges of the piston? And I'm not talking about only modded trucks. Have seen several stock trucks with this failure.

Tapamaxxing
 
Too much timing and or pressure combined with hoter than stock egt...boom.

Those are the rattle trucks...fuel is making it all the way out there because the piston is too low in the stroke.

Less timing...and it would have not happened.
 
homewrecker said:
80k lbs through the Rockies at 1000hp making 100lbs of boost. His truck can do things no other can do. Didnt you know that by now. It's all he spats off about on here.

So back to late model re-entrant pistons and different spray angles.
Tapamaxxing
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He's top chief at TrailerTowingDiesel.com :doh:
 
homewrecker said:
My question is why with the narrow spray angle on a wide bowl does it seem that most melt downs are on the outer edges of the piston?
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Now you are asking the right question.

cquestad said:
Those are the rattle trucks...fuel is making it all the way out there because the piston is too low in the stroke.
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Do the math on how much timing would need to be used to spray on top of the crown in a 3" bowl with a 124° cone angle and you will quickly realize that is not the issue.
 
Plenty of failures can be directly attributed to a poorly operating injector. No matter how good the nozzle is or was.

Test benches tell a shop very little in terms of injector calibration. We test plenty of injectors that deliver the proper amount of fuel, but the calibration is off enough to have an injector delivering that fuel either late or too early. Timing retarded, advanced or the shot being to rich at the tail end as examples. CR injector health testing is 99% set up and calibration. Bench testing should only be used to evaluate the work you did previously ( calibration and measurement of very critical dimensions ) and hydraulic parameters are good. not leaking, etc.

There are plenty of parameters that can be incorrect internally, but still test good on the bench/stand. This is because one out of calibration component can mask a deficiency in another area. Today in fact we had some dealership replaced injectors come in for check out. The customer recently had the dealer replace the originals. The Cummins recon facility uses good parts, but in too many cases the measurements are off enough to cause running issues. 3 of the 6 had armature lift specs way out of whack. This was not from wear. There really was no appreciable wear. It was from a sloppy calibration by the technician, or worse yet contamination when they were assembled. The problem can worsen when the armature lift is incorrect because they seem to typically crutch the issue by changing the solenoid air gap. Although the injectors delivered the correct quantity, they did it at the wrong time. Even a truck that runs well could have a poorly calibrated injector or injectors.

We have seen a large number of "reman" injectors come through our shop lately with injector calibration specs that are far out of order. These injectors will have a very limited service life. Either they used inadequate parts, got the torque specs wrong, the calibration was wrong or a combination of all.

If the injectors are not measured and recorded as properly assembled and calibrated before bench testing, the best you can hope for is the hydraulic side is tested for leaks and perhaps a rough idea of the injected quantity. Nothing more.

Lastly, these things are stressed by many people beyond what they can handle for extended periods from pressure, poor fuel, etc. They are a marginal design to begin with. These stresses wear parts and pieces out of calibration and even if the truck is running ok, the injectors can still have enough faults to toast a piston.
 
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Don, do you see these same issues in new or remans coming directly from Bosch?
 
nwpadmax said:
Don, do you see these same issues in new or remans coming directly from Bosch?
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Rarely, in fact it is so rare it is not even funny. I have had a few per month tops. It is rarely an armature lift spec that is too high, but rather slightly too low. This is done to add more life to the injector. As the control valve seat wears, the armature lift increases. If you set it lower to begin with, you get fewer returns later. This is great for a stock injector and works good for most performance injectors, but every now and then, it is low enough that it effects driveability and balance rates. We are talking about microns here. Usually 2 microns low. The Bosch injectors are assembled in self contained units by robots. They rarely make a mistake. The stock Bosch injector drawback is more along the lines of not being set up for performance rather than a calibration issue. Much like a blueprinted engine assembled by hand for a purpose VS a stock engine built by machines. The edge usually goes to the blueprinted engine.
 
Yes we have tried other manufacture's and other angles, nothing has been within 400hp of the exergy stuff.
 
Smokem said:
Do the math on how much timing would need to be used to spray on top of the crown in a 3" bowl with a 124° cone angle and you will quickly realize that is not the issue.
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I did it because I was bored, and I like math. I don't have the distance for how far below the head surface the tip of the injector is or the air gap between the top of the piston and the head. All that said, here's what I came up with. A 124 degree spray angle will spray right at the edge of the bowl when the timing is at 26.5 degrees. A 143 degree spray angle will spray right at the edge of the bowl when the timing is at 21.5 degrees. For curiosity's sake, I checked when the spray would hit the cylinder wall. With the 124 degree spray angle, it will hit at 31 degrees of timing, and with the 143 degree spray angle, it will hit the cylinder wall at 25 degrees of timing.
 
JoshH said:
I did it because I was bored, and I like math. I don't have the distance for how far below the head surface the tip of the injector is or the air gap between the top of the piston and the head. All that said, here's what I came up with. A 124 degree spray angle will spray right at the edge of the bowl when the timing is at 26.5 degrees. A 143 degree spray angle will spray right at the edge of the bowl when the timing is at 21.5 degrees. For curiosity's sake, I checked when the spray would hit the cylinder wall. With the 124 degree spray angle, it will hit at 31 degrees of timing, and with the 143 degree spray angle, it will hit the cylinder wall at 25 degrees of timing.
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Josh that sounds low, was this on a stock piston bowl or aftermarket, and what bore.
 
JoshH said:
I did it because I was bored, and I like math. I don't have the distance for how far below the head surface the tip of the injector is or the air gap between the top of the piston and the head. All that said, here's what I came up with. A 124 degree spray angle will spray right at the edge of the bowl when the timing is at 26.5 degrees. A 143 degree spray angle will spray right at the edge of the bowl when the timing is at 21.5 degrees. For curiosity's sake, I checked when the spray would hit the cylinder wall. With the 124 degree spray angle, it will hit at 31 degrees of timing, and with the 143 degree spray angle, it will hit the cylinder wall at 25 degrees of timing.
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I always like when someone is interested enough to put in some personal effort. That being said your values are a good bit on the low side.
 
JoshH said:
I did it because I was bored, and I like math. I don't have the distance for how far below the head surface the tip of the injector is or the air gap between the top of the piston and the head. All that said, here's what I came up with. A 124 degree spray angle will spray right at the edge of the bowl when the timing is at 26.5 degrees. A 143 degree spray angle will spray right at the edge of the bowl when the timing is at 21.5 degrees. For curiosity's sake, I checked when the spray would hit the cylinder wall. With the 124 degree spray angle, it will hit at 31 degrees of timing, and with the 143 degree spray angle, it will hit the cylinder wall at 25 degrees of timing.
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325hpCR_zpsfc001484.jpg


Utilizing the 143° marine nozzle would put the pattern on the edge of the lip at roughly 45° advance on the piston above.

It is nice to see someone else actually put in the effort and try.
 
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TheNatural31 said:
325hpCR_zpsfc001484.jpg


Utilizing the 143° marine nozzle would put the pattern on the edge of the lip at roughly 45° advance on the piston above.

It is nice to see someone else actually put in the effort and try.
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Static Timing Advance is only a part of the equation...What PSI is this calculation being derived from? I figured between 50-60* advance given 28k RP
 
DIESEL_POWER said:
Static Timing Advance is only a part of the equation...What PSI is this calculation being derived from? I figured between 50-60* advance given 28k RP
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You are close, utilizing the 124° nozzle.
 
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DIESEL_POWER said:
Thats a large margin...sure everything was apples to apples?
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Of course not, we are not a laboratory, we are constantly just looking for the next edge, and as much as we would always love to change one thing at a time just to see, that isn't the way it works, especially when our track season lasts from May to October. However it was 140mph to 149mph at about the same weight.
 
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