My Injector Project and What I’ve Learned

ndamico

Vendor , w/Business number
Joined
Mar 20, 2008
Location
Sacramento, CA
TDI
2003 Golf 2Dr TDI, 2003 Jetta TDI, 2003 Jetta Wagon TDI, 2002 Duramax, 2003 Duramax
I was planning on releasing everything I’ve learned at a later date but due to some mud-slinging I’m being forced to do this sooner rather than later. Please take this as you would anything else. It is not a secret that after this testing I decided to try and make a better nozzle, especially for higher horsepower applications. Some of you will probably argue that I’m biased or perhaps even made this up and that’s up to you. Anyone who knows what Bosio vs. Bosch nozzles cost plus paying for machine work will see that I’m not in this to get rich.


To give you guys a little background- I’ve been into diesels since 2002. I’ve owned 3 Duramaxes and currently own two as well as 2 A4 Jetta TDI’s. I’ve been into competition since 2003 and currently have one Duramax with a fully-built race motor that is basically dedicated to drag racing and sled pulling. My other Duramax is a dually which I use to tow the race truck around. I’ve had a lot of experience with different diesel performance parts- turbos, injectors, cams, heads, studs, transmissions, etc. I’ve broken quite a few things during the development of many of the parts that are sold today for the Duramax. I’ve even manufactured a couple different things and still sell a few products for the Duramax. Up until last year I owned and operated dieselplace.com, the largest Chevrolet & GMC diesel truck forum in the world.


If you would like to know more about my truck and what I’ve accomplished with it please see:

http://www.wackywack.com/dmax.htm


When I bought my TDI’s my goal was to find the best parts I could for my two cars. If I found something I didn’t like my plan was to utilize my experience and industry connections to improve upon what is currently available. Last year I decided I wanted to put bigger nozzles in my cars. I looked at what was readily available and found Bosch, Bosio, and some Chinese nozzles sold on eBay. I also found DSS nozzles but they didn’t seem to be readily available over here so I didn’t include them in my testing. Based on what I had read on the club (which I’m sure comes to no surprise) it seemed that Bosio was by far the most popular choice. I procured the following different nozzles, each set being brand new in the original packaging (I even tested several sets of the same type of certain models):


Bosch 706
Bosio PP357
Bosio Sprint 520
Bosio PP520
Bosio PP502
Bosio PP764
Bosio Race 520 5-hole
Bosio Race 520 7-hole
Chinese eBay nozzles


Here is a picture of one of the Bosio boxes I received. They all looked identical and had the same distributor’s sticker on them. I hope this is the best way to assume they are all genuine. I also purchased them from several different vendors on the forum so they wouldn’t come from just one source.



I then sent them off to have them tested. My initial hope was that they would say the Bosio’s were superior and I would then pick the size I wanted and move on to my next project. However that was not what I found.
To give a little background of what type of testing I had performed- Each nozzle was internally inspected for surface finish (inside the nozzle, not outside), potential EDM manufacturing damage, spray pattern, and consistency of flow. To make this simple I’ll use a Bosch 706 nozzle as my baseline. We tested several sets of these nozzles and every one of them flow tested exactly the same. The spray patterns were perfect and there was no sign of manufacturing defects. Bosch EDM’s their nozzles initially then briefly hones them to remove any small imperfections from the EDM process.

Bosch 706 nozzle pictured below:



The Chinese nozzle was not surprisingly the least-desirable of those tested. We found the holes were actually drilled and not EDM’d. There was no evidence of EDM damage as that process was not utilized. The spray pattern was not as uniform as the baseline nozzle but surprisingly not horrible either. The major downside was the variance in the flow from nozzle to nozzle. I only tested one set of these and they flowed 35.714%, 78.571%, 43.264%, and 61.119% over stock for a set average of 57.143% over stock. One of the big things that make a great truck nozzle is to have each of them flow as close together as possible so you get an even distribution of fuel for each cylinder. It’s easier on the motor, especially when you are trying to make a lot of horsepower.


All of the Bosio nozzles were EDM’d so I won’t cover that aspect for each one.


The PP357’s showed no internal manufacturing defects from the EDM process. The spray pattern was good as was the surface finish. They flowed 21.429%, 28.571%, 35.714%, and 42.857% over stock for a set average of 32.143% over stock.


Two of the 8 Sprint 520’s tested showed burn marks from the EDM wire over penetrating the hole and residual slag material from the EDM process. The spray pattern was good and other than the EDM damage the surface finish was fine. The first set flowed 28.571, 35.714, 42.857%, and 42.857% over stock for a set average of 37.5% over stock. The second set flowed 35.714, 39.286%, 41.429%, and 42.857% over stock for a set average of 39.821% over stock.


Bosio sprint 520 pictured below:



The PP520’s showed no internal manufacturing defects from the EDM process. The spray pattern was good as was the surface finish. The first set flowed 50%, 46.429%, 57.143%, and 57.143% over stock for a set average of 52.679% over stock. The second set flowed 50%, 46.429%, 53.571%, and 57.143% over stock for a set average of 51.786% over stock.


Bosio PP520 pictured in both photos below:




The PP502’s showed no internal manufacturing defects from the EDM process. The spray pattern was good as was the surface finish. They flowed 64.286%, 67.857%, 71.429%, and 71.429% over stock for a set average of 68.75% over stock.


The PP764’s showed no internal manufacturing defects from the EDM process. The spray pattern was good as was the surface finish. They flowed 92.857%, 89.286%, 85.714%, and 71.429% over stock for a set average of 84.821% over stock.


The Race520 5-hole nozzles showed no internal manufacturing defects from the EDM process. The spray pattern was good as was the surface finish. They flowed 128.571%, 125%, 135.714%, and 128.571% over stock for a set average of 129.464% over stock.


The Race520 7-hole nozzles showed no internal manufacturing defects from the EDM process. The spray pattern was poor in that it would load too much fuel to one side of the cylinder. See photo below. Since the nozzle sits at an angle in the head the holes are staggered differently as you move around the circumference of the nozzle. The extra holes are staggered incorrectly which also negatively affects the spray pattern. It was recommended that I not put these nozzles in my car. They flowed 164.286%, 157.143%, 207.143%, and 164.286% over stock for a set average of 173.214% over stock.


Bosio race520 7-hole pictured below:



Another piece of interesting information was that the while the Bosch and Chinese nozzles were clean inside about 40% of the Bosio nozzles had to be cleaned before they could be properly evaluated. They suggested this was due to the way in which they were packaged. Both the Bosch and Chinese nozzles came sealed in individual plastic tubes. I would also like to point out to date I have never installed or ran any Bosio nozzle in my car. I’ve driven plenty of cars with them but have never run a set myself. I want to be clear that all of the data I have is from the testing which was not done from a vehicle.


After getting all the results back I noticed 2 things. The first is that all of the nozzles except the OEM Bosch units weren’t matched well for consistency within a given set. Some were better than others but none were close to the OEM Bosch. I then decided to try and create some nozzles of my own. I had 3 choices for a starting point and I looked into what I could buy them for near dealer pricing. From least to most expensive they were 1) Chinese nozzles at approx $15 each, Bosio nozzles at approx $30 each, and Bosch nozzles at approx $60 each. I then have processing fees to cover the EDM and Micro Extrude Hone work which for the most part price me out of the current market. I was told the best nozzle to start with was the Bosch as it had a slightly better surface finish and they felt the seat area was also slightly better.


Next I purchased several sets of brand new OEM Bosch nozzles from a Bosch dealer in Wisconsin (was the best price I could find. My dealer here was $80 each). I have since made several sets of varying sizes which have been put into several people’s cars, some of which are club members. So far we have had great results. We have been able to hold the flow numbers very tight. The last step is they get extrude honed to remove imperfections, polish the inside of the nozzle, and radius the inside of the holes where the fuel flows. That is what makes the pictures of them looks so nice and shiny on the inside. My nozzles are reworked in the USA and they are done one at a time and each one is flow tested as well as cleaned. Given the price point some mass-produced nozzles are designed to meet I feel there is room for improvement when price is not such a main consideration. I include Bosch copper sealing washers as well as clear plastic tubes so you can submerge your old nozzles in WD-40, biodiesel, etc. I’m not making these nozzles to try and make a fortune. I’m doing it because I think I can make a better product that may appeal to some people. I can also make custom sizes for non-standard applications. Essentially I’m not limited to a pre-set number of configurations.


One of my nozzles pictured below:



Before the testing I had collected information as to where each Bosio nozzle fell with respect to size. I was a little surprised by the PP357 vs. the Sprint 520 as well as the PP502 vs. the PP764. Since these did not come out as I had expected I have decided to post a recap of the Bosio’s tested from smallest to largest.


Bosio PP357 ------------ 32.143% over stock
Bosio Sprint520 --------- 37.5% over stock
Bosio PP520 ------------ 52.679% over stock
Bosio PP502 ------------ 68.75% over stock
Bosio PP764 ------------ 84.821% over stock
Bosio Race 520 5-hole ---129.464% over stock
Bosio Race 520 7-hole ---173.214% over stock


As I said during my introduction I wasn’t planning on posting any of this information yet. However I am being publically accused of selling, “crudely re-worked bossch 706 nozzles”. I also had someone call me and say the same individual is telling people I’m using drill bits to enlarge stock Bosch nozzles. All of this is coming from a vendor who has never touched with his own hands or seen with his own eyes a set of Bosch nozzles I’ve had reworked. It’s after these comments that I decided to write this thread.


I’ve been around forums for years and especially from having owned one I know the politics run deep; much deeper than most people ever know. One is forced to learn the hard way whom you really can and cannot trust. I for one don’t appreciate my efforts being belittled as I'm sure none of you do either. If you don’t like what I’m doing you’re entitled to that opinion but don’t be childish and make up lies in an attempt to discredit me.


So for the record I’m not telling all of you to go buy my nozzles. I haven’t even advertised them on the club, in my signature, etc. I’m just laying out everything I’ve done and learned and hopefully some of you will learn something from it too.

Thank you

On Edit- I forgot to add that I have tested Bosch PD100 and PD150 nozzles as well as Bosio Race783 PD nozzles. It wasn't the focus of this thread but I have done the testing on them. To summarize the results briefly:

A PD150 nozzle flows 23.077% more than a PD100 nozzle. A Bosio Race783 flows 178.846% more than a PD100 nozzle.

The set of PD100 and PD150 nozzles I tested all flowed exactly the same within their respective sets. The Race783's showed no internal manufacturing defects from the EDM process. The spray pattern was good as was the surface finish. They flowed 184.615%, 184.615%, 176.923%, and 169.231% over a stock PD100 nozzle for a set average of 178.846% over a stock PD100 nozzle.
 
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Growler

Got Soot Vendor
Joined
Nov 24, 2003
Location
Millersport, Ohio
TDI
Schmutz, 2015 Golf Sportwagen DSG & Schnurren, 2001 Golf GL 2 door 5M
Who was that Masked man..

Glad to see this thread come out. I've been hearing exciting news of someone coming out with some new nozzles. And the guy I recommend to people for balancing has been telling me about some of the things you mentioned in this thread.

One thing I am unclear on.. is the Bosch706 the Stock 5 speed nozzle? or where does it land in the comparison compared to the Stock 5 speed nozzle?

Looking forward to the future. It's gonna be exciting.
 
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KROUT

persona non grata
Joined
Aug 26, 2005
Location
JAX FL
So this is interesting because the pp502's are supposed to flow more than the pp764's. So if your test are accurate and unbiased that's not the case.
 

caloony

Veteran Member
Joined
Apr 10, 2009
Location
Toronto, Ontario
TDI
2003 Golf TDI GLS
Wow...I wish I could afford every single set of nozzles! Im joking, thank you for all that info, very well done and well written (with detail)
 

vwmikel

Vendor , w/Business number
Joined
May 5, 2005
Location
Las Vegas, NV
TDI
'94 Golf Sport TDI
KROUT said:
So this is interesting because the pp502's are supposed to flow more than the pp764's. So if your test are accurate and unbiased that's not the case.
I can confirm that when tuning a car with either of these nozzles, the pp764's always smoke more (so fuel has to be reduced) when used with a stock turbo. The PP502's can remain fairly smoke free with full fuel requested, but the PP764's would clear intersections.
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
SOLD 2010 Touareg Tdi w/factory Tow PCKG
Great data!

http://pics.tdiclub.com/data/500/Tdi_Nozzle_data_and_comparisons.pdf


Notes:

I'd like to shrink down the PDF so that it is centered on text but don't know how (still learning the mac).
One of the Sprint 520's passed with a good rank but the other set failed to deliver spray uniformity. I've arbitrarily said that 10% coefficient of variation is the limit of acceptability (marked in red text with conditional format rule), but I really don't know. More experienced tuners/users hot rod people can speak with more authority. Based on what VWMikel and others are saying, it seems like a reasonable line in the sand to me.
Coefficient of variation is just the standard deviation (spread) over mean. It's a measure of precision.

Thanks very much to ndamico. Now we have a means of ranking/comparing your new nozzles too. :) It's a great day for performance Tdi peeps.
 
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Farfromovin

Torque Addict
Joined
Apr 9, 2005
Location
Ventura, CA
TDI
03 Golf 2dr- PD150 6m
First off, thanks for the wonderful effort you've gone in a quest for nozzles. That's a lot of work. As per this quote below, I had a question:
ndamico said:
On Edit- I forgot to add that I have tested Bosch PD100 and PD150 nozzles as well as Bosio Race783 PD nozzles. It wasn't the focus of this thread but I have done the testing on them. To summarize the results briefly:

A PD150 nozzle flows 23.077% more than a PD100 nozzle. A Bosio Race783 flows 178.846% more than a PD100 nozzle.

The set of PD100 and PD150 nozzles I tested all flowed exactly the same within their respective sets. The Race783's showed no internal manufacturing defects from the EDM process. The spray pattern was good as was the surface finish. They flowed 184.615%, 184.615%, 176.923%, and 169.231% over a stock PD100 nozzle for a set average of 178.846% over a stock PD100 nozzle.
Which injectors were the PD150 and Bosio Race783 nozzles mounted on? When will you have flow data of your "reworked" nozzles? I'm sure a lot of people will be quite interested.

That being said. Kudo's to you for standing up and doing something to stop the mud slinging process (doing what you can at least).
 
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KROUT

persona non grata
Joined
Aug 26, 2005
Location
JAX FL
vwmikel said:
I can confirm that when tuning a car with either of these nozzles, the pp764's always smoke more (so fuel has to be reduced) when used with a stock turbo. The PP502's can remain fairly smoke free with full fuel requested, but the PP764's would clear intersections.
Well shoot I need to see if Paul will trade out my new pp502s for pp764's. I was under the impression they were slightly larger.
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
SOLD 2010 Touareg Tdi w/factory Tow PCKG
KROUT said:
Well shoot I need to see if Paul will trade out my new pp502s for pp764's. I was under the impression they were slightly larger.
As were most of us:mad:
 

BioChoppers

Vendor
Joined
Aug 8, 2007
Location
Whittier, California
TDI
2003 jetta 5spd wagon
KROUT said:
Well shoot I need to see if Paul will trade out my new pp502s for pp764's. I was under the impression they were slightly larger.
We have tuned many sets of PP502's & I always wondered why they didn't smoke more & seemed so much slower than the PP764's.

The other interesting finding is that the sprint520's flow more than the PP357's.

[FONT="Trebuchet MS", Arial, Helvetica]S520[/FONT] [FONT="Trebuchet MS", Arial, Helvetica]SPRINT 520[/FONT] [FONT="Trebuchet MS", Arial, Helvetica]$240.00[/FONT] [FONT="Trebuchet MS", Arial, Helvetica]$240.00[/FONT]
[FONT="Trebuchet MS", Arial, Helvetica]PP357[/FONT] [FONT="Trebuchet MS", Arial, Helvetica]POWERPLUS 357[/FONT] [FONT="Trebuchet MS", Arial, Helvetica]$357.00[/FONT] [FONT="Trebuchet MS", Arial, Helvetica]$357.00[/FONT]
That's $117.00 everyone could have saved over the years!
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
SOLD 2010 Touareg Tdi w/factory Tow PCKG
One thing that stands out to me is how I can see a cottage industry springing up to simply buy ten of each nozzle type and create matched sets for a nominal fee ;) No joke. I bet a guy could make a nice supplemental income just testing and creating matched sets.

ndamico, can you test a few sets of Sprint 764 nozzles too? Please post up your nozzle results as soon as you can.

Thanks.
 
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IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
Thanks for this thread. It puts in perspective what some people have been seeing lately regarding lower power from PP502s than expected. What concerns me is the variation from nozzle to nozzle. My goal with the Golf is to generate the most power I can from an ALH but with exceptional reliability. Down time means lost track time. Logic would indicate that having nozzles that are as equal as possible is going to be superior variations from cylinder to cylinder.

My question: Is the nozzle to nozzle variation you saw on, say, the PP520s significant? If so, what would be the consequences?

EDIT: As an aside, I have a set of Bosch .205s I purchsed from Dieseldorf some time ago. They came from Red Rotors in Canada originally. I have them set to pop at 190 bar and they're in my A3. Every time I drive the car I'm impressed by how smooth it is. Hmmm.
 
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danielhf

Veteran Member
Joined
Mar 27, 2007
Location
Seattle, WA
TDI
None anymore...
Hats off to ndamico! It's about time that the mud slinging and conjecture in regard to nozzles has finally amounted in something useful and dare I say it, scientific.

There is obviously a great deal of work that he has put into this project to not only possibly provide this community with an extremely high quality new product, but also provide us with stringent factual data on nozzles that we have been using in our cars without much question (until recently) for years. Just look how PP502s have been regarded in comparison to PP764s, and that's only the most obvious thing to consider at first glance.

Rather than basing our ideas about TDI performance on gossip and questionable vendor allegiances, let the science and facts speak for themselves! Reading this post was like finally seeing the fog surrounding the elusive nozzle "debate" clear and turn in a logical direction.
 

ndamico

Vendor , w/Business number
Joined
Mar 20, 2008
Location
Sacramento, CA
TDI
2003 Golf 2Dr TDI, 2003 Jetta TDI, 2003 Jetta Wagon TDI, 2002 Duramax, 2003 Duramax
Sorry, i guess i wasn't clear. this was a test of the nozzles alone. they weren't mounted on bodies. to that would require considerably more time and expense and since i'm not in a position to actually modify the flow characteristics of a body it wouldn't help me much. my guess with people not seeing a ton more fuel with a big race bosio PD nozzles is that they are a physical limitation of the body. we've had that problem with truck nozzles too. eventually you run out of "injector" to drive your nozzle.

Farfromovin said:
First off, thanks for the wonderful effort you've gone in a quest for nozzles. That's a lot of work. As per this quote below, I had a question:

Which injectors were the PD150 and Bosio Race783 nozzles mounted on? When will you have flow data of your "reworked" nozzles? I'm sure a lot of people will be quite interested.

That being said. Kudo's to you for standing up and doing something to stop the mud slinging process (doing what you can at least).
 

ndamico

Vendor , w/Business number
Joined
Mar 20, 2008
Location
Sacramento, CA
TDI
2003 Golf 2Dr TDI, 2003 Jetta TDI, 2003 Jetta Wagon TDI, 2002 Duramax, 2003 Duramax
I never managed to acquire sprint 764's but if you have a couple sets of brand-new ones i wouldn't mind doing that.

as far as my nozzle's go, I have plenty of data right now. there are several people here running them. i just didn't want to make my thread look like a sales pitch so i only showed one of my nozzles :)

i have about 9 different variations so far. granted a lot of them are huge ones that would apply to very few but i don't want to exclude any big HP guys!

nicklockard said:
ndamico, can you test a few sets of Sprint 764 nozzles too? Please post up your nozzle results as soon as you can.

Thanks.
 

greenskeeper

Top Post Dawg
Joined
Mar 10, 2003
Location
USA
TDI
1998 Jetta TDI
Maybe I am missing something here, but how can you measure flow without the body/nozzle combination?

If all 4 injectors are balanced to pop at the same bar, wouldn't they flow the same or no?

DBW should chime in on this....
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
Saw that, but you said that's your arbitrary rule. I have no idea whether or not 10% is fine or catastrophic.
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
SOLD 2010 Touareg Tdi w/factory Tow PCKG
ndamico said:
I never managed to acquire sprint 764's but if you have a couple sets of brand-new ones i wouldn't mind doing that.

as far as my nozzle's go, I have plenty of data right now. there are several people here running them. i just didn't want to make my thread look like a sales pitch so i only showed one of my nozzles :)

i have about 9 different variations so far. granted a lot of them are huge ones that would apply to very few but i don't want to exclude any big HP guys!

Please share that raw data with me by PM, as the cat's already out of the bag. Good luck getting her back in ;) Ain't gonna happen. :p Don't tease us like this. Show me the money!(numbers)

Also please share with me the total cost of the bosch nozzles so I can add them to the comparo. With the data already given above by you, what we have here is a performance-price envelope that, essentially, you forced yourself to compete within. I'll get it all in one place and put them on a nice bar chart set, 3-D surface plot, or radar plots. I personally DO think there's room for another vendor if QC is a high concern ;)

*Note: I got the prices for nozzles on kermatdi.com about 1.5 hours ago and the higher of the prices for the chinese ebay nozzles at ebay.com about 1.5 hrs ago too.
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
SOLD 2010 Touareg Tdi w/factory Tow PCKG
IndigoBlueWagon said:
Saw that, but you said that's your arbitrary rule. I have no idea whether or not 10% is fine or catastrophic.

Well the point I glean from it is that the PP357's and Chinese nozzles tested were complete crap, the center of the precision envelope was the PP series (except 357's) and the Race 520-2's. Sprint 520's were hit or miss with one very good and one pretty bad, and the premium end of the line were the PP502's and Race 520's (best).

Within the middle of the precision envelope (just looking at flow uniformity), all of them are close to my arbitrary 10%

So although the 10% is definitely not confirmed, it gives a useful starting point for users to compare various flavors of nozzles.

The flow characteristics are harder to qualify/quantify as we'd need independent reports for that.
 

dieselpower04

Veteran Member
Joined
Jun 26, 2007
Location
Outside Tampa, FL
TDI
2004 Golf GLS TDI (sold)
ndamico said:
On Edit- I forgot to add that I have tested Bosch PD100 and PD150 nozzles as well as Bosio Race783 PD nozzles. It wasn't the focus of this thread but I have done the testing on them. To summarize the results briefly:

A PD150 nozzle flows 23.077% more than a PD100 nozzle. A Bosio Race783 flows 178.846% more than a PD100 nozzle.

The set of PD100 and PD150 nozzles I tested all flowed exactly the same within their respective sets. The Race783's showed no internal manufacturing defects from the EDM process. The spray pattern was good as was the surface finish. They flowed 184.615%, 184.615%, 176.923%, and 169.231% over a stock PD100 nozzle for a set average of 178.846% over a stock PD100 nozzle.
First off great work!! I am with Phil on this. I was asking in another thread about having Race783 nozzles on PD100 injectors. I, as well as other PD owners, would love to know.

How/could you be able to test this? I know you said you didn't test with the injectors themselves, but maybe some who is knowledgeable in the art of injector/nozzle assembly could do this and hand off to you to test?

I'd even be willing to donate beer to the cause!!:D
 

chimaera

Veteran Member
Joined
Dec 28, 2006
Location
Ireland
TDI
2012 Skoda Superb Combi CR170
greenskeeper said:
Maybe I am missing something here, but how can you measure flow without the body/nozzle combination?

If all 4 injectors are balanced to pop at the same bar, wouldn't they flow the same or no?

DBW should chime in on this....
Once the injector body can supply enough fuel for any of the given nozzles, it ceases to be a variable in nozzle performance. This is a comparison of the nozzles' ability to flow fuel through them. Fundamentally a nozzle with bigger holes will allow more fuel through than one with smaller holes. This analysis quantifies this difference.

The opening pressure of the injector is independent of the nozzle. The opening pressure is determined by a spring mounted inside the injector body. The nozzle doesn't come into play until the injector has already opened. The flow rate through the nozzle is then brought into play and unless all 4 nozzles are matched, you'll get different flow rates through each one.
 

KERMA

Vendor , w/Business number
Joined
Sep 23, 2001
Location
here
TDI
99 beetle and 04 jetta
So, I guess I was right, that other 275 post thread is all about bashing kerma and bosio to set the stage for nicktane. Let me explain the meaning of the word "crude".

How did you measure to 4 significant figures accurately?

the bosio edm is purpose-built for injector nozzle manufacturing, and has the ability to change the size of the hole profile during the edm drilling. in other words, the inner diameter is larger than the outer diameter in some cases, and there's a chamfer added to the inner surface at the flow entry, just like the Bosch.

The flow numbers listed above for the Bosio are all wrong. Every Bosio nozzle is flowed in ml/min of test oil at 100 bar and 40°C with Shell oil V 1404 according to ISO 6584 comma 3 sub comma 431 test standard using a very expensive state-of-the-art machine that was built especially for Bosio. The flow tolerance is set to within 1% for the sprint, 0.5% for the Powerplus, and 0.2% for the race. The machine can hold tolerance less than 0.1% if needed. This oil flow is measured in the same direction as the normal flow of fuel during use an a car, IOW, from the inside out.

I wonder how the Nicktane measures nozzles. When they talk in liters per minute, that tells me compressed air at 50 psi, which is the "golden standard" with the truck nozzle guys. They connect a rubber hose to the outside of the nozzle tip and flow air in the reverse direction, in the tip and out the entrance. Adjust the air regulator to 50 psi, and guess the height of the metal ball bouncing up and down in the flow meter and "call it". One prominent vendor was quoted in a diesel mag as saying "we like to get the flow within one" (liter per minute of compressed air at 50 psi) For reference, we are talking about roughly 20 liters per minute for sprint 520 nozzles using this method. "within one" is +/- 5% if you can get it consistent each time, not counting the error from the flow gage, temperature differences, compressible medium, etc.

At Bosio EDM is cut into a fresh nozzle with no hole using CNC edm. tolerance at this stage is +-6%, which is slightly looser than the finished bosch. There are 3 steps to the "honing" after the initial EDM. initial flow measurement/cleaning, hydro-grinding, and cleaning/verification.

The hydro-grinding is done using a media with the same viscosity and flow characteristics as diesel fuel, but it contains proprietary sub-micron sized abrasive material suspended in the oil. The flow is measured in real time as the nozzle is matched to the target flow. there is very little material removed during this process, which intended more as a de-burring than anything.

THis is the way Bosch nozzles are made at the Bosch factory, and the process is state-of-the-art.

WHen the bosio nozzes are packaged, a heavy grease type material is applied to the inner and outer surfaces to stop corrosion. That's what is seen and it doesn't have to be cleaned for the nozzle to be useable as it is soluble in diesel fuel.

EDM burn? it's in the wrong place on the nozzle. seems fishy.

I'll have to assume the nicktane manufacturing and test procedure is similar to what the truck guys have been doing for years:

EDM machine is typically one that's been previously used for medical equipment, and drills one hole at a time. The "real deal" costs about 400 grand and none of these guys can afford that. They take a genuine Bosch nozzle, and line up the machine with each hole individually, and drill with the edm electrode to make the hole bigger. There is no ability to vary the profile through the depth of the hole, and the leading edge tends to be rough. You can make the holes any size you wish, however. Extreme care must be taken by the operator, because even the 0.5 degrees misalignment in any axis will destroy the integrity of the original hole. It's not uncommon to see "twinning" or a figure eight on the inside of an aftermarket EDM'ed nozzle. When this happens, the operator will just pretend it's all right, and send it on to the customer anyway, because he doesn't want to eat the cost of a new nozzle, and if it smokes: "it's a high flow nozzle, what do you expect"

The extrude honing process uses a much higher viscosity media than the test oil, and it is an iterative process. Flow is measured, then the operator estimates the flow time based on the media used and the operator's experience. The cutting media is forced through the nozzle for the calculated time, then the nozzle is cleaned and the flow measured. If it's close enough, done, if not, it may be cut again with a different lower viscosity media. The heavier the media, the more it cuts. If the operator overshoots one nozzle, he may just ignore it and go on to the next one, or try to bring the others in line, which means increasing the flow on the other 3 to match. But that's more work, and unless the customer is a very special one, or paid extra, errors of a few percent are just considered part of the game.

Extrude honing is not in itself bad, because every major manufacturer uses some form of "hydro-grinding" to polish and deburr the flow passages. But this hydrogrinding is only for the last 5% or so of the flow, and to match the nozzles to a flow standard. The problem comes from trying to cut too much. the seat of the needle gets cut, and the needle won't seal as well between injections. This causes a nozzle to not chatter and it could even stream fuel or bleed down between injections.

It also affects the outside if the hole in a drastic way. Here is an example of a nozzle that's been cut far too much:




This is my definition of "crude" It's a relative word, and I think it's appropriate in this case.

I'm sorry if that word offends you, Nick, but I don't think it begins to balance out all the 275 posts in that other thread, laying the groundwork for your new product release, savaging both the competing product and me personally.
 
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KERMA

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Summary: the flow numbers are bogus. Anyone who has ever tuned a TDI knows that PP357 don't flow 30%+ more than stock!! And r783 sure as hell don't flow 178% more than stock! (closer to 50%, actually)

Measuring flow with compressed air at 50 psi flowing backwards through the nozzle = :rolleyes:

Measuring flow with temperature controlled test oil with precision measuring equipment, flowed the correct direction through the nozzle, following and iso test standard = :D

Measuring flow iteratively, after cutting, precision and accuracy unknown = :rolleyes:

Measuring flow in real time while hydrogrinding, repeatable measurments within 0.1% and precision/accuracy within 0.02%= :D

Massive cutting into the seats with thick media to get the most flow increase= :rolleyes:

Getting the basic shape and flow correct with EDM, followed by polishing with low viscosity hydro-grinding = :D
 

vwmikel

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While everything you say makes perfect sense Charlie.....the thing that I'm stuck on, and I think most of us are, is the control.

If his testing methods are faulty then why did the Bosch nozzles all flow the same? Surely if it were inaccurate then those would've had their share of deviations as well.

I agree that testing with oil would be better than testing with air (I don't know how he tests them), but when it comes down to it all that you really need to know is the baseline and the new flow rate with the nozzles being matched up as a set. You could measure that in liters per hour or camels per hour, it wouldn't make a difference. :D
 

KERMA

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anyone who's ever taken an introductory statistics course can tell you this established fundamental condition:

you need at least 32 samples in order to have a standard normal distribution.

in other words: 4 random samples out of thousands doesn't tell you anything. And these samples could be cherry-picked to achieve some pre-determined outcome.

And if the measuring technique is invalid or inappropriate, how can you trust the result at all.

If I need to machine a shim of exactly 20.4723 inches thickness, do I use a precision laser to measure, or a harbor freight caliper and a yardstick? Would calling it twenty and a half inches be close enough? About 2 feet? You certainly can't take a yardstick and caliper and reliably determine thickness to ten thousanths. (although I know one machinist who said he could lol)

If you are making a stake for your farm tent , then "about 2 feet" is probably ok.

If you are shimming an aerospace part, more precision and accuracy is probably required.
 
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vwmikel

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KERMA said:
anyone who's ever taken an introductory statistics course can tell you this established fundamental condition:

you need at least 32 samples in order to have a standard normal distribution.

in other words: 4 random samples out of thousands doesn't tell you anything. And these samples could be cherry-picked to achieve some pre-determined outcome.

And if the measuring technique is invalid or inappropriate, how can you trust the result at all.

If I need to machine a shim of exactly 20.4723 inches thickness, do I use a precision laser to measure, or a harbor freight caliper and a yardstick? Would calling it twenty and a half inches be close enough? About 2 feet? You certainly can't take a yardstick and caliper and reliably determine thickness to ten thousanths. (although I know one machinist who said he could lol)

If you are making a stake for your farm tent , then "about 2 feet" is probably ok.

If you are shimming an aerospace part, more precision and accuracy is probably required.
I agree that larger scale testing would be better for DEFINITE solutions, but the analogy just doesn't really hold water. If you're using the same inaccurate methods for everything then even the control would be inaccurate.

The problem is that variance works both ways. If I am measuring said piece of wood and lets say my yard stick has a tolerance of 0.1 inches then even if the wood was exactly 20.4723” then I might get a result anywhere from 20.3723” to 20.5723”. Finding 4 pieces of wood that measure out at exactly 20.4723” means that I would basically have to get very lucky in measuring THAT piece of wood THAT particular time. I wouldn’t get the same repeatable results each time.

Any decent testing rig would obviously be tested for repeatability.
 
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