VP44 PSG5 limitations read/write

[rogerash0]

JL Im gonna call Don this am & see if he has any 200-240 horse injectors on the shelf. I say that bc last I spoke to his wife they had 150s on the shelf. Do you think Don's F1 injectors will really fall short of Infinite or Hailey? Perhaps its hard to know. 

 

Wasnt TFaroro running some giant 6x.018s and he stepped down to 6x0.013s? Im just trying to get a feel if I run dons mach 5,6 or 7 (200/220/240hp) I plan on taking your advice on the size, but getting a 7x.011 or 7x.012 since 6 hole doesnt seem to be an option, and mathematically those both boarder on 6x.013. Ill ring infinite and haileys first, see if that gets anywhere.

 

Edited October 24, 2017 by rogerash0

[pepsi71ocean]

I have had multiple sets of DAP injectors I've used on builds, and I've never had issues with any of their stuff.

I understand that there was a lot of scuttlebutt with the common rail injectors, but that isn't what I do, i play on VP's

[rogerash0]

ha, scuttlebutt. cool. Don's wife tells me my injectors will ship tomorrow - F1 Diesel - Don said at sea level /w my setup the Mach 6's which are 200hp injectors will get me 620hp. His wife said they start out as 7x.011's, but what sets them apart is how they open up the holes. It sounds like they get chamfered along the 'outside' radius. So they flow more, roughly. I thought that sounded like plenty of HP, so instead of going to 220 or 240hp injectors, I went with the 200s. It was along the lines of thinking the trucks get crankier with big injectors, but I could be wrong there too. 200 is already big, so I thought less might be more. Time will tell. Another big factor is how TFaroro stepped down from something like roughly 300hp injectors, 6x.018s I think, to 200hp 6x.013's. I need to find that thread again somehow. Unfortunately it might be buried in the details of his build.

[kzimmer]

I keep looking at updates on this thread hoping to find some neat new info about the read/write limitations about the VP44.

[rogerash0]

From what I got someone was saying you are limited by the 12 bit bus (2^12), not being able to send the vp44 a higher fueling value, >4096, but I have to think in the firmware of the bosch test bench that programs the vp44 ram (I dont think it would be rom if its getting re-written to via the bosch test bench, altho I think some rom chips can be re-written to but its really not my area of expertise), it sets the amt of fuel injected for each value between 0 & 4096 via something like rpms, voltages, resistance to a circuit, some kind of fuel delivery valve that opens for so long, etc. So that more fuel could be injected. Conventional wisdom would say the pumps have some overhead or have more juice in them than what they are programmed for due to emissions. But we really need a firmware engineer who worked on the pumps who's seen the source code to really know. And even then, a firmware engineer may not know what the mechanical engineers put together. But even still, testing could be done. I have to think there are people out there who could reverse engineer it from a bosch test bench. Since the source code is probably locked away in a vault, have a test bench dump the payload onto a chip we can read from and analyze, but that's really getting into the weeds. Perhaps manipulating a test bench to manipulate the output written to a vp44 would be an eaiser endeavor, if the test benches wernt too expensive. Seems too niche unfortunately. Not to mention Bosch would take to the courts Im sure. Defcon videos on reverse engineering WoW, atms, etc get pretty interesting.

Me said:

the pump gets a 0-4096 command for fueling, then decodes that into a pulse for the fueling solenoid.  

 

 

that overhead you are talking about is what wiretap does.  the limit is ~%20-%25 more duration from the solenoid.  

 

 

But really we are talking about reinventing the wheel here, why not just get bigger injectors?   Bigger injectors effectively increases the amount of fuel injected in the fueling pulse. 

 

I have to think your right. One thing Ive always wondered tho, is when you have way bigger injectors, is how the pump keeps the same fuel pressure coming out of injectors that are massively bigger than stock. I suppose the pump could have the overhead built into the chambers (ya I made that word up, I dont know what the correct verbage is, plunger barrels perhaps) to push large injectors at stock pressures, but I tend to doubt it. Whats the deal here/there?

[Me78569]

The pump delivers much more fuel per stroke than a 400hp truck can use.  

 

It starts to run out of steam around 600hp in terms of actual fuel pumped.  Remember that the injectors pass unused fuel back to the tank via the port on the back of the head.

 

 

My truck with 7 x .012's and a he351ve drives REALLY nice.  the vp shows no signs of not being able to keep up.

[rogerash0]

Impressive, I thought those injectors would be huge for a he351ve but shows what I know. I think thats the magic in the Quad adr v2 tuning, right?

 

Also how does the excess fuel leave the injector? I dont see a hole in the injector tubes or injectors for the fuel to flow out in the path of a return. I have put a new washer on the back of the head's banjo bolt, so I am familiar with the return line.

Edited October 25, 2017 by rogerash0

[Me78569]

see the hole above the feed tube hold in the body of the injector.  the fuel comes out of that into the area of the head that the injector tube onring seals the system.

 

 

If you use ricer math, 

 

7 x .012's = ~200 hp over stock.  

 

235 + 200 hp = 435 hp 

 

Add in canbus duration increase of %12 

 

435 * 1.12(%12 over stock) = ~490 hp 

 

The he351ve flows 69 lb / min of air at the peak of it's map.   Thats right in the 450-500 hp area.    

 

 

 

There is no magic in the v2, BUT it is my theory that since others tuners work above stock fueling only, they overfuel down low causing a overshoot on the turbo, sling shotting it out of it's map.  causing heat etc.  By controlling fueling down low better you are able to keep a turbo in it's map and not vastly overfuel the turbo under the curve.  

Edited October 25, 2017 by Me78569

[rogerash0]

Cool, thanks for showing me that. Do u know why a fuel return on the injectors is needed? They pop at x amt of pressure right, so the vp can't get it exactly dead on every time at the right time? I guess not bc of what we see in the CR engines.

 

The over fueling down low is what drives me nuts.

[trreed]

4 hours ago, rogerash0 said:

300hp injectors, 6x.018s I think, to 200hp 6x.013's

He had a set of DAP 7x.013's and recently went to a set of Infinite 6x.013's that he's very happy with last time he and I talked.

[jlbayes]

Don's injectors really muddy the waters as he tends to favor smaller hole size. However they work extremely well in a 24v. Both ppump and vp fed. I have no doubts you will be happy with whatever he sends you. Infinite and Haley are just my go to's. I communicate with both on a regular basis. And a "200hp" injector is not that big in the scope of things, imo. @Me78569 is catching on as to why I like bigger than most. Boy that last statement could take a turn. Good thing I did not say it on fb lmao

[rogerash0]

Quote

Don's injectors really muddy the waters as he tends to favor smaller hole size. 

By this do you mean that Don does really well unconventionally with the smaller hole size, and still gets great results?

 

Objectively speaking, for a daily driven truck, and I leaving power out of the equation by not getting his 220 or 240hp injectors? I dont know the quad well enough to know if I could clean up those bigger injectors, and/or if the bigger injectors would lead to a crankier truck? Do the injectors over 200hp empty the VP too easily? That's why you have the holley lift pump? Do you think it would be sensible or wise to put a holley lift pump after my airdog to keep fuel pressure steady at the VP? I suspect my VP pressure will drop from 25psi idle to 8psi WOT with my AD 4G 200 /w with these larger injectors. I know the holly may not handle the inlet pressure so well, but I suppose it is quite adjustable on the Airdog.

 

(ive started to not like the injector hp rating either, the hole sizes & # of holes sounds more precise) 

 

7*.011 is very close to 6*.013, so I stuck to your suggestion on size as close as I could. His wife also said they start out as 7*.011's but will flow more than that.

 

& thanks Treed

Edited October 25, 2017 by rogerash0

[Me78569]

From what I have found I think you can run as big as you want and not have real issues.  I would buy injectors based on your power desires.    If I am able to clean 7 x .012's at 7000' altitude you should not have any issues cleaning 6 x .013's or similar in great falls.    

 

I dont know what you mean by "drain the vp to easily"  a lift pump, assuming positive inlet pressure, won't prevent the vp from running out of the ablity to push fuel at the limits.  even at 8 psi the VP won't run dry.  

 

 

[jlbayes]

17 minutes ago, rogerash0 said:

By this do you mean that Don does really well unconventionally with the smaller hole size, and still gets great results? Yes

 

Objectively speaking, for a daily driven truck, and I leaving power out of the equation by not getting his 220 or 240hp injectors? I dont know the quad well enough to know if I could clean up those bigger injectors, and/or if the bigger injectors would lead to a crankier truck? Do the injectors over 200hp empty the VP too easily? That's why you have the holley lift pump? Do you think it would be sensible or wise to put a holley lift pump after my airdog to keep fuel pressure steady at the VP? I suspect my VP pressure will drop from 25psi idle to 8psi WOT with my AD 4G 200 /w with these larger injectors. I know the holly may not handle the inlet pressure so well, but I suppose it is quite adjustable on the Airdog. I had no issue dd'ing the 6x.013s I had. I also never had a problem with them emptying the rotor but I learned to not drop off the throttle fast. I have the holley lift pump as the airdog would not feed my power level at the inlet pressure I wanted. For the relatively low pressure a vp requires there is no reason the airdog you have drops pressure. 

 

(ive started to not like the injector hp rating either, the hole sizes & # of holes sounds more precise) 

 

7*.011 is very close to 6*.013, so I stuck to your suggestion on size as close as I could. His wife also said they start out as 7*.011's but will flow more than that.

 

& thanks Treed

 

Diesels are fun aren't they LOL

[notlimah]

On 10/24/2017 at 8:09 AM, jlbayes said:

Not my group fyi lol

 

What group is this?!

[rogerash0]

hmm ya. It seems like I need to watch for voltage drop at the airdog as i accelerate. Not sure how to do it, that would take some really long meter leads. I guess a backprobe and some wire would work. Odds are its just a bum motor, I suppose. The brand new 165 and 200gph motors, both. I was driving totally tame today, not blowing smoke but on level 6, and the vp fuel pressure is 21-22 just humming along at 1300rpm. And my fuel tank is 90% full. Its ridiculous. It just slowly drops as you step into the pedal. I am getting anxious to put the old school 100 motor on there, which came on the truck and never dropped pressure on me previously, and see what it does.

35 minutes ago, notlimah said:

 

What group is this?!

2nd Gen Cummins Nation!

Joined

8,947 members

Edited October 25, 2017 by rogerash0

[trreed]

5 hours ago, jlbayes said:

Diesels are fun aren't they LOL

Sometimes......... Not.

[jlbayes]

17 hours ago, notlimah said:

 

What group is this?!

 

Lemme know who to look for and I'll let you in.

[rogerash0]

Who can tell me how to keep the brights and normal headlight on at the same time. Like when I pull the lever back for brights but don't click it they ate both on and it's way better. I'm driving at night cross country thx

[Mopar1973Man]

You can do a bright box or there is either a relay mod or wire mod. I've never done either because the extra load on the headlight circuit becomes excessive usually causes issues with switches.