Over Sized DV Holders

Can you just answer and stop avoiding the question?
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Careful Don....
You will get the obligatory two paragraph answer that never says anything and only speaks to his use of the same magic fairy dust the Left Coast dyno crowd uses.......Andy
 
I posted on this subject quite a bit long ago asking many questions. Ive since been running the opened up holders ever since, I gauged the opening myself at the time at around .025" and had them opened to .093". In therory i seen it flowing lots more fuel, and in reality it very well may still do so? Dont know. But i do know it never picked me up any E.T. or mph. The final restriction is always going to be the injector nozzle, but my thinking as to why to open them up was to have that orfice larger than what the nozzles would flow.....so does that single .025" orfice flow more than say a 5x18 nozzle would?????? Dont think so. Ive already stated I seen no gain from them, but if I had it to do over I would have still opened them up, just because my reasoning still makes since to me also.
Ryan
 
stock600 said:
The final restriction is always going to be the injector nozzle, but my thinking as to why to open them up was to have that orfice larger than what the nozzles would flow.....so does that single .025" orfice flow more than say a 5x18 nozzle would??????
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Thats exactly what I was thinking, but didnt want to post it for fear of lookin like a moron LOL because at this point the extent of my knowledge of both the P7100 and the injectors, doesn't get much past basic knowledge and general concepts :doh: Along that same line of thinking though, I can see how possibly the larger holders and lines may help during extreme sistuations such as sled pulling, where large quantities of fuel are called upon for extended periods of time. For example 20-30 seconds during a wide open run on the pulling track vs. a 5-10 second snap on the dyno.
 
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stock600 said:
I posted on this subject quite a bit long ago asking many questions. Ive since been running the opened up holders ever since, I gauged the opening myself at the time at around .025" and had them opened to .093". In therory i seen it flowing lots more fuel, and in reality it very well may still do so? Dont know. But i do know it never picked me up any E.T. or mph. The final restriction is always going to be the injector nozzle, but my thinking as to why to open them up was to have that orfice larger than what the nozzles would flow.....so does that single .025" orfice flow more than say a 5x18 nozzle would?????? Dont think so. Ive already stated I seen no gain from them, but if I had it to do over I would have still opened them up, just because my reasoning still makes since to me also.
Ryan
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The reason you saw no gain is because the holder is not restrictive. Opening them up only increases wear on the injectors, the delivery valve itself, and can cause a plunger to hang if you have a DV stick or leaky DV seat. I measured a 20-25 HP LOSS with modified holders in 3 different sizes. Going up to .065" using a 13mm pump and a stock 215 pump cam.

Here is the clue: Do you really think (Like Jim Fulmer does) that a pump would last one minute trying to pump a slug of fuel as large as it does at WOT through a hole that is only .025" in diameter? The pump would fail before you made it out of the staging lanes.

Several people get on here and say "the DV holder opening is only .025" and the line is .078 - .093" Those people are wrong.

Like I said, get a small gage screwdriver and a stock 215 holder in your hand and get back on here when you do.
 
Like I already said, I gauged mine myself at .025". I dont follow others hype, I do what makes since to me and do all my own work. They obviously didnt slow me down but not sure they helped either. But i also run a 180hp pump so I dont have near the fuel that lots do exp. the 13mm guys. Is there a differance between the 215 holders and the ones that i mic'ed on my stock 180hp pump?
Back to the question in post #53.
Can the .025" orfice [in at least a 180hp holder] flow as much or more than say a 5x18 nozzle? My area math says no, but im always up for learning something new. All my weekly data comes from E.T. and mph, not flow bench numbers, quesses, dyno numbers or amount of feet pulled. Quite repeating the same sentence over and over and get to the point, its not rocket science.
 
I'm very interested in this thread and would like to see some real world data myself. I'm thinking of going back from 191 dv's to 181s as well as I have no aspirations to be a puller, only drag race on occasion.
 
Soup Nazi said:
The 215 holder is good for all the stock pumps. 160, 180, 215. Actually a 13mm pump is fine with a 215 holder too.

My point here is to try and explain why the 215 holder should not be modified and to let everyone know the holder is not restrictive. That is an urban legend. Paying to have a set of holders modded is a waste of cash. The first person to get a 215 holder and a small gage screwdriver in their hand wins a prize.
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I don't have one in my hands at the moment, but heres a picture of a holder from my truck (215) next to a .093 holder. Maybe you can tell us what you are talking about now...
DSC00732.jpg
 
Good photos. We already know the pump would seize if it was forced to push fuel through that little .025" opening. Not to mention the pressure drop that would occur, even if the thing was able to live long enough to measure it.

Bosch designed the DV holder to operate in two directions. To NOT allow the fuel to return into the delivery valve and plunger area with much force and on the other hand TO allow the fuel to be pushed toward the injector without restriction. This is accomplished by allowing the restriction button to raise up on the outgoing side. It is spring loaded and begins to open around 100 PSI if I remember correctly from 2003.

The area that opens up below the restriction button is plenty large to allow all the fuel a 12mm or a 13mm pump can move with a stock cam pump profile.

The stock DV holder is taller than the open style holder from Bosch because it has to be. This is to allow the spring and button the room it needs to operate.

If you take a small gage screwdriver or similar and a DV holder you can physically push the button up with moderate force. We built an expensive fixture designed to hold the DV holders to flow test them with ISO test fluid 4113 using around 1000 PSI of pressure. This was before we figured out the button was raising up off its seat and the restriction would go away. Turns out the pump and electric motor we used was nowhere near large enough to support 1000 PSI once the button lifted. We were lucky to get 200.

So what happens if the restriction is not there? What if the hole is opened up in the DV holder? It depends on the line size, rack position, RPM, opening pressure of the injector, etc. In many cases on the test bench we found the nozzle would pop open long after the injection event was supposed to have stopped. This would cause fuel to spray directly onto the cylinder wall. Not a good scenerio for a street engine.
 
What are everyone's thought on 181dv's for a street driven street strip truck under 700hp? Seems to me the fastest guys, atleast in the 160 pump world, are running a 181 or 131 dv. I don't know if the 215 pumps are different but my GUESS is no.
 
IIRC CDS mods the button also in some way shape or form.....
Brandon
 
Smokem said:
You say increasing the throttle bore size adds wear to the injectors and delivery valves, then in your next statement you contradict your previous comment. Why would Bosch offer a standard open style delivery valve holder if damage would occur? One reason for the pintle on the retraction piston of the delivery valve is to dampen pressure reflection.
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Not all systems have the problem associated with the P7100 we use. Depending on the cam profile, the rate of its lift, the plunger size, etc the pressure developed with an in-line pump can vary from 350 bar to 1300 on some of the larger "ZWM" sized pumps. Injector line size and length and injector size can also change what is needed, if anything, to control wear at the injector or the DV. Even the plunger assembly can be effected negatively. Many plungers can be caused to rock in their barrel/bores from uneven pressure applied to them. Either from a single helix cut in the plunger ( this is why all 800 bar and up pumps run a double helix design, to even the pumping pressure and its relief on port closure ) or from excessive pressure wave reflection coming toward its face.

Yes, the return flow restriction ( the .025" valve plate ) inside the DV holder is there to stop wear and cavitation as explained above. There is no contradiction in statement. Just different designs for each system of pumps, DV holders, DV's, lines and nozzles. The wide open holders are not used in a system exactly like the P7100 on the Dodge/Cummins.

Plungers that stick or hang in their bores can be directly increased to do so more frequently by a negative pressure wave from the closing injector at the opposite end of the line.

I went down memory lane tonight and found 3 of the DV holders we tested. They are stamped 1238. I may go outside and open the hood on my truck and see what they have stamped on them as well. I have not found DV holder the test fixture we had machined from stainless steel yet.

My plan is to drag all this mess out and visit it again.
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NickTF said:
What are everyone's thought on 181dv's for a street driven street strip truck under 700hp? Seems to me the fastest guys, atleast in the 160 pump world, are running a 181 or 131 dv. I don't know if the 215 pumps are different but my GUESS is no.
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I ran .022's on a 215 pump running high 11's to 12.0's. I switched back to 181's and ran the same with less egt and smoke. They might be needed in sled pulling, but not so in drag racing.
 
f6jbob said:
I ran .022's on a 215 pump running high 11's to 12.0's. I switched back to 181's and ran the same with less egt and smoke. They might be needed in sled pulling, but not so in drag racing.
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Man that's the kind of info I was looking for!

You know it's not hard finding people who run 215s into the 11s no doubt because these pumps came on manual truck. If you don't mind pm me the details of your setup! :Cheer:
 
I went straight to 181's, then to full cuts (which sucked).. I'm now running 131's in my 160.. It only made one pass before the intermediate went, but it ran a smokeless 11.71 on diesel only with egt's around 1200.. It's not the fastest thing in the world, but something about not worrying about smoke when driving it puts a smile on my face..
 
97' CTD said:
IIRC CDS mods the button also in some way shape or form.....
Brandon
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Yep, they have it figured out! Don't think anyone can questions what they can do with a pump, they had it figured out long ago.

Brad you now understand why I like 181 DV's so much.

Jim
 
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