UDC tuning for vp trucks!!??

[Mopar1973Man]

Duration... I wish the term would go away.

The fuel pin creates line pressure making the injector fire multiple times as a chattering effect in a sense duration but line pressure it what makes it fire several times. If you could place a pressure gauge on one line and watch VP44 goes from about 4,500 to 18,000 PSI per line. (Not exactly sure the max pressure... close to the 20,000 range)

Back in the days of 1st gen it was really common to blow a injector line after turning up the fuel screw and installing a aggressive fuel pin. The lines could handle the pressure break or crack.

 

 

Edited March 22, 2016 by Mopar1973Man

[Me78569]

so when you hold the fueling solenoid open longer ( wiretap) it allows more fuel to be put into the plunger and thus pushed though the lines.  

 

Does injection pressure actually increase more as you hold the fueling solenoid open longer?

[Mopar1973Man]

Just now, Me78569 said:

Does injection pressure actually increase more as you hold the fueling solenoid open longer?

Yes.

[Me78569]

interesting.  wouldn't figure it would significantly.  

 

The more you know.

[TFaoro]

To an extent though right? Larger injectors allow more fuel to flow out thus releasing pressure

[Me78569]

That is what I would expect.  

 

I would think you could make up the difference with larger injectors.  I will browse through the cf cummins forums.  a lot of old posts are running edge ez with big injectors.

 

In theory, smarty + 150 injectors should have the same numbers as a edge comp + 50 - 75 hp injectors 

[TFaoro]

That's all in theory though. I would like to see what mine would make with only the smarty on these injectors. I wonder if they would be close to the 125s and the TST/smarty stack

[Mopar1973Man]

2 hours ago, TFaoro said:

To an extent though right? Larger injectors allow more fuel to flow out thus releasing pressure

That's the problem. The pressure falls off very rapidily instead of hold a nice crisp fog pattern it turns more of a splattered mess. Larger the droplet the more to to convert from liquid to vapor ot Bang! Hence why more and more people battle with SAC injectors and controlling smoke because the pressure drop is pretty rapid because of the high volume nozzle. I will admit that SAC is the ultimate injector for power production but not very good for street manners. Where in reverse the small nozzle hold pressure in the line longer and keeps the better fine mist to fog going. Which in turn produces cleaner power better street manners but more limited on fuel flow.

This why CR engines are able to do it better because that can preload the cylinder with fuel mist then light it off with the main event allowing for more fuel to placed in the cylinder but still keeping a good fog to mist going. Also CR engine have higher pressures over VP44.

 

Edited March 22, 2016 by Mopar1973Man

[TFaoro]

6 minutes ago, Mopar1973Man said:

Hence why more and more people battle with SAC injectors and controlling smoke because the pressure drop is pretty rapid because of the high volume nozzle.

I have no idea why people battle this. I can run mine virtually smoke free with a smarty. It's all in the right foot. Same goes for fuel mileage.

[Mopar1973Man]

Like myself I can drive with the Edge cranked up on 5x5 I've done it too. It about giving lag to spool up the turbo. Again back to fuel management most on the human side. ISX did it with his p7100 pump and remove the plate and AFC. Again all done on the human side allowing time for the turbo to light up.

But for the puppies of the world that plant their boot to the floor at the green light will fight the smoke issue. There was no finger point at you @TFaoro speaking very generally.

Now @Me78569 with his turbo controller might be a whole another game changer too.

Edited March 22, 2016 by Mopar1973Man

[Me78569]

I can still smoke like a vegas slot machine jockey.  

 

That's a big reason I am curious about the udc pro stuff.  you could pull fuel from the bottom.   

 

in a dream world I would throw a opacity sensor on the tailpipe and pull fuel when it was smoking beyond a point.

[AH64ID]

All I can really add is that custom tuning is so much more than box tuning. It's not even a fair comparison, even if the dyno shows the same numbers. 

 

Depending on the number of unlocked tables the hp limit may change without a tap or external module... If the table can be modded and the parameters changed, well you get the idea. 

 

That is where custom tuning is different than box tuning. While something may be possible with a box tune the results from truck to truck may be inconsistent so the parameters are "safer" or "milder". 

 

I do see a difference in here than in the CR world. In the CR world of tuning I like slightly oversized injectors so we can reduce the duration and thus the timing. 

 

I also saw a comment in here about pilot timing. Last i saw guys with EFI are killing the CR pilot at higher rpms and loads. It's something I plan to mess with once 5.9 UDC Pro is released. 

 

According to to the news release the VP trucks are next after the 5.9 CR trucks. That's before the 6.7 3rd gen trucks. 

http://madselectronics.com/downloadfiles/News.pdf

Edited March 23, 2016 by AH64ID

[CSM]

Well.  I guess that means I am getting a pro eventually.  Question is if I should sell my S03 now or not...  should I be looking at the smarty or that other brand?

[NightHawk]

In all this discussion, there hasn't been much talk on how the vp pump will react to the custom tuning options if made available. Looking in that regard, these pumps are not high flow/rpm by design so pushing them "beyond" what has been done already seems like an uphill battle.  Granted, having control over low end smoke levels and to better "calibrate" large injectors to the pump will be awesome features but don"t discount the mechanical limitations of the pump itself.

[CSM]

True, it aint a cr.  However, if I can exactly tune it rather than some level or catcher... Id be happy.  The quad has interested me in that regard.

[TFaoro]

Quad has definitely helped with keeping my smoke to a minimum except at WOT. As of now I'd say it is the best on the market.

[Me78569]

Csm don't do any jumping until we see what they actually do for us.  They may not release anything new at all.

 

Remember the limitations of the mechanical side of the pump is pushed by a wiretap not by the can bus fueling.  The so can fuel to 600 hp without issues.

I very much doubt that the udc pro will even come close to stressing the pump by itself.

[Mopar1973Man]

11 minutes ago, Me78569 said:

I very much doubt that the udc pro will even come close to stressing the pump by itself

I would say BlueChip or Quadzilla would be the biggest modules that could stress the pump. Bluechip more so...

http://www.bluechipdiesel.com/redline_box.html

[NightHawk]

9 minutes ago, Me78569 said:

Remember the limitations of the mechanical side of the pump is pushed by a wiretap not by the can bus fueling.  The so can fuel to 600 hp without issues.

I very much doubt that the udc pro will even come close to stressing the pump by itself.

The discussion has strayed towards rpm on several posts, while the vp can support "600hp" per say and I use in quotations for a few reasons...the fueling available at rpm is the question.  

The quad, redline, tst comp & edge drag comp all allow for increased rpm, but the vp fuel curve seems to drop off hard after 3500-3800.  The design of the pump it stock form does not allow for a lot of plunger refill time before injection events (or so I have read) so that's why the "monster" pump, dragon flow of schield lighting have been created.

 

[Mopar1973Man]

Thank you bring that video forward. I knew that Stainless made over 1000 HP on fuel only on VP44.