Calling Dave ( PP ), Malone And Dr. D GTD vs Merc injectors

[Tintin]

DNOSD261 = 0 434 250 120

Which is the difference between DNOSD261 and DN8S2 ?

[subsonic]

Who the heck knows.  Everytime I call Bosch or mercedes or vw, no one will tell me the flow rates of any of their nozzles.  Is this some kind of top secret, secret squirrel ***?  I was just looking for more flow than stock 1.6 or 1.9 injectors.  People pointed to the 300TD injectors, but no one had data, They just seemed faster.  The injection shop guys told me the DN8S2 flowed a hell of a lot of fuel, like two to three times stock.  Again no data.  No one I know has run them yet.  Named Tintin, have you run the DNOSD261 that you posted about? Is there some way to find out flow rates from these?  If you hooked up the injector to a pop tester could you measure the quantity of fuel it dipenses at it breaking preasure?  Does this remain constant, or does the rate change over the rpm scale?
Who has a inside man at Bosch that will give up some basic freaking information! :x

[scopefrfd]

I called a place in MS and asked for a price on DN8S2 nozzles $43.  He was very curious what I wanted to use this in.  I told him a Benz and he stated "you donn't miind meltin stuff" southern drawl.  He states those injectors are for very high HP engines..engines I never heard of.  And seriously doubts that the pump will be able to fuel the nozzles and it probably won't idle.  He also stated that bosch doesn't make a bigger nozzle than this and they do not rate pintle injectors by flow rate.  Bosch doesn't give out that info.  You'd have to get the info from either a bosch engineer or a engineer that uses that nozzle in their engine.

[foxracer1]

So could we find out the "stages" or different sizes they offer? Maybe a little higher up than the factory injectors? I still would like to try an run these.  
:twisted: 12mm giles super pump pushin these injectors, PP intake/DP/cam, with twin chargers to back them up!  :twisted:

And seriously doubts that the pump will be able to fuel the nozzles and it probably won't idle. He also stated that bosch doesn't make a bigger nozzle than this

That makes me want them even more! :twisted:

[scopefrfd]

I called 4 places and the price was all the same at $43.  So I assume that's the list price.  If we could get these things for $25 I'd buy a set.  $43 is a little high

[subsonic]

Yeah baby! Go big or go home!  That would be almost the same conversation I had with the injector guy in my area.  He did not know flow rate, but knew they were WAY more than stock.  He mentioned stuff I hadnt heard of either.  I think they must be European. Any of you guys inEurope heard of these?   Is there really a danger of melting pistons?  I was told that the injector bodies for this setup ran at 125 bar.  How would we go about measuring flow rate on this nozzle?  Is this somthing Giles could help with?

[scopefrfd]

I wondering about a couple of things...the engines the diesel tech I was talking to was referring to big farm/tractor engines.  Are the pre-chambers on those engines much bigger than a vw unit?  I would assume so?  What if the nozzle spray pattern is so large that pre-chamber converts it back to a liquid because of its smaller size which would not be good.  

The tech also advised that the breaking pressure is not set to the nozzle but rather the application.  Which makes sense..vw uses the same nozzle for usa 1.6D and td but with different break pressure.  A nozzle that flows this high, I think a higher break pressure would be better than a lower one.  Especially since the pintle would barely be coming off it's seat at idle a higher pop pressure would itemize the fuel better.  I assume one would have to run a 11mm or 12mm pump anyway.  why not raise the pop pressure to 175-195 bar.  

May be able to create the ultimate 1.7td with 1.9tdhead or a 1.9td with this nozzle.  I suggest the 1.9 head because of the bigger pre-chambers and better flowing head.  It will also reduce compression which with these nozzles may be critical as I'm sure one would have to run 30+psi of boost to make this thing work...do I hear a vnt turbo spooling up??  I wish I knew this earlier I have a set of Bosio GTD nozzles sitting on the shelf waiting for me to finally assemble my 1.7td with 1.9td head.

[Tintin]

Why not take nozzles of 6.2/6.5D GMC?  Very easy to find, and not expensive.

[Turbinepowered]

Why not take nozzles of 6.2/6.5D GMC?  Very easy to find, and not expensive.

I seem to recall hearing someone say they won't fit in the injector bodies?

[Audi80]

What is wrong with stock injectors :?:

[Tintin]

humm!!, the old Redrotor's MK2 jetta 1.6TD had nozzles of 6.2 or 6.5.

My friend who has to buy this car, the removed it, that made a bad idle and poor performance (black smoke).

[subsonic]

So I was wondering, just how much fuel is too much?  I know that is a application specific, but as a reference.  As a base for this question I nominate the 1.9td head.  It will be going on a 1.6, but not sure if that makes a difference.  I read here somewhere about the volume of the pre-chambers.  Can anyone figure out what the maximum amount of fuel that can be burned given this volume.  This may take some wierd math to figure out.  Is there a specific burn rate of fuel? How much time does it have to complete its burn during the piston revolution?  Would propane quicken the burn time?   Breaks over... back to work.  See ya later.

Jim

[Tintin]

I do not know how much fuel is too much for IDI prechamber.

I bought Mercedes nozzles (261)  best than I could measure the hole, they seems to be 0.10mm larger than the GTD nozzle, that appears small, but I sure that made a considerable difference in fact.

I do not have time to test them before this week end, on AAZ.

[935racer]

I've tried the Mb nozzles a few times they are great, I think it was the 6.5 nozzles I also went to try but they weren't even close to fitting, they could have been 6.2 nozzles though.

I would just use the MB nozzles and call it good. There are a ton of other things that will give you a lot more gains and a lot of other things to be concerned about than nozzles on an IDI (as long as they are clean and rebuilt that is).

[Turbo DS]

There are a few ways you may measure the flow rating, and one such way is by using a calibrated test stand.  Another method to yield results arises from injecting a fixed pressure via a pressure chamber released by a solenoid valve, and time the valve to open only for a short, fixed temporal interval.  The injected quantity would then be measured in a proper vessel, so the results could be observed.  

It may be possible to fit the nozzles with a far lower spring seat pressure, for test safety, and ease of collecting the injected quantity.  When comparing subsequent nozzles, it would be optimal to use the very same spring rate for the same resulting opening pressure.

Of course, a possible easier method is simply to fit the test nozzles to an engine, and measure the results on a rolling road, before and after the test nozzle are installed, assuming other variables could be held constant.

An excellent benefit for those running high charge pressures (I am running >45 p.s.i.), comes from an increase in breaking pressures of the injectors.  This is due to better, and more proper atomization from the increased charge pressure to atmospheric pressure.  However, if the opening pressure is increased, an inversely proportional relationship exists with the injected quantity.  A simple way to maintain the injected quantity is to increase the nozzle’s aperture.  Depending on the increase in diameter, you may maintain the previous injected quantity before the increase in opening pressure, or hopefully exceed this value.

Another detail that might pose problems for us, lies within the Bosch number itself.  I’ve read that it should contain the nozzles theta for the spray cone.  Ideally, it should at least be the same as the stock fitted nozzles.  Does anyone have access to these metrics for the nozzles 0 434 200 012, 0 434 250 120 and the stock fitted nozzles?