DAP Injector Upgrade 7 x 0.010 @ 320 Bar

[Mopar1973Man]

7 hours ago, Shainer said:

Question for the guys that have a Quad and suspected weak pop off pressures.  So here is my deal.  I have DAP 7x.095 aftermarket injectors.  I estimate I have maybe 100k miles on them.  Frankly I've been a little suspect of their performance from day one.  I noticed my idle RPM's have been trending upward.  Last few years I noticed idle hovering around 850.  I just took a look my idle RPM's over the past few days and now it settles in at around 870.  Any time I try to cruise at around 1000-1100 RPM I experience what might best be described as surging (manual trans with ceramic/kevlar clutch).  Life is busy so I just put up with it, except now it seems to be getting worse.  You know how it is, not bad enough to deal with... until it is.  So now I'm determined to improve this situation I was thinking about the low RPM cruise surge condition.  Get on my old forums and poke around, initially thinking it may be IP related.  Then I find this thread, and it got me thinking it could be one or more injectors are popping early causing uneven combustion spikes.  The 1000-1100 RPM range is kind of a resonant frequency for the condition.  Then I see you guys reporting on idle engine load.  Something I never paid any attention to.  The past few days when idle is sitting in that 870 range my engine load reports 0-5%.  1-4% being the norm.  I honestly would have figured that to be a normal range... but maybe it isn't?  Does what I describe sound like low pop pressure?  I performed a compression test a few years back.  Don't remember the numbers but do remember there was no more than a 5% deviation.  I think I have my injection timing cranked higher than I expected too.  Maybe capped at 20-21 degrees, not a hint of rattle.

Any thoughts are appreciated.  

 

 

Classic low pop pressure. My stock injectors did the same them engine load dropped out and idling near 850 to 900 RPMs. 

 

7 x 0.010 @ 320 bar idles lower like 780 to 800 RPM with a 13-14% engine load. 

[pepsi71ocean]

1 hour ago, Dieselfuture said:

Are they vco or sac, at 100k they will definitely be low on pop especially if you didn’t ask dap to set them higher from the start. If it was me I would repoop them to 320 and make sure flow is still good. I was very surprised when I put it in my 7x10 vco 320 bar in, smooth idle and no smoke at all. I just wish they wouldn't settle that fast. 

 

I second the 320 Bar pop pressure.  My Dodge with my smarty never ran so clean as it does since I popped them. My idle is so smooth the tach signal doesn't even move now lol

 

Personally mine were popped to 322bar, but I think that when it comes to popping them higher that one needs to do it based on the size of the Injectors. I don't think 60hp Injectors will do well at 320 bar compared to say 100s at 320 bar.

Edited February 14, 2019 by pepsi71ocean

[IBMobile]

So what it come down to is number of holes (X) times size of holes (.Y")  at pop pressure (Z bar) will equal a smooth running no smoke engine.  If this is the case then it should be graphable. 

[dripley]

I see yall speaking of engine load while idling. My scan gauge shows 0% while idling. It has for quire some time. Is the scan gauge II the least bit accurate for that measure?

Edited February 14, 2019 by dripley

[Cowboy Doc]

 I am curious to see the answer to @dripley's last question.

 

I have to say this thread is the most informative I've ever come across on a forum.  Good stuff.   I've been on the edge, leaning towards an injector upgrade (now that I have reliable fuel supply) just b/c I'm intimidated by tuners (sorry, but true).  Will pull the trigger on iQuad when I get back next month.  Only question I have is, for the downloadable tunes on this site, are they sorted as to what sort of upgrades you may or may not have installed?  LIke, if I go to search for a "DD" or "tow" tune, will it say if it was tweeked according to stock injectors vs, say, 7x010's?  Or do I just have to start with one and go through a process of fine tuning for results? 

[Shainer]

12 hours ago, Dieselfuture said:

Are they vco or sac, at 100k they will definitely be low on pop especially if you didn’t ask dap to set them higher from the start. If it was me I would repoop them to 320 and make sure flow is still good. I was very surprised when I put it in my 7x10 vco 320 bar in, smooth idle and no smoke at all. I just wish they wouldn't settle that fast. 

Thanks for the response.  SAC.  They would have been set at factory pop off pressure.  As for settling in, or dropping pressure.  IMHO they should not have any significant deviation at 100k miles.  Raises quality questions.  I have tested 12 valve style injectors with considerably more hours, and typically usually don't see much pop off pressure degradation.  Maybe it is the nature of these injectors, seems odd to me though.  

3 hours ago, dripley said:

I see yall speaking of engine load while idling. My scan gauge shows 0% while idling. It has for quire some time. Is the scan gauge II the least bit accurate for that measure?

I'm sure Mike can speak with much more authority on this, but I'm pretty sure the ECM generates that calculation.  So scan gauge or Quad just displays the data stream.  Do you ever see it come off 0% at maybe the first start of the day, or when the grids or AC compressor cycle?

[dripley]

6 minutes ago, Shainer said:

I'm sure Mike can speak with much more authority on this, but I'm pretty sure the ECM generates that calculation.  So scan gauge or Quad just displays the data stream.  Do you ever see it come off 0% at maybe the first start of the day, or when the grids or AC compressor cycle?

Comes off 0% when I am on the throttle from 0 tp 100%. But I still see 0% at idle. My grids are disconnected, but never looked while the AC was on. I was just surprise a few days ago that my AC still worked when the temps shot up here the other day.  Replaced the compressor and some other stuff and was not sure it was going to hold but it did. Victory for me.

 I will check that tomorrow and see what load it might show. I would expect to see some load at idle, but again dont know how good the SCII is at reading load.

[Shainer]

Guess I will fork over $500 for a new set of 7x0.010 SAC.  How does a guy get DAP to bump the pop pressure up?

 

I"ll get my 7x0.095 SAC's reset and release them to the wild.

[Me78569]

only some 2nd gen trucks report engine load correctly.  

 

 

As for bumping pop pressure PLEASE PLEASE PLEASE only do so if you want to mess with it, and you accept that it may not work or start when cold.  there is not nearly enough data to support that popping higher is a good idea.  

 

 

[Dieselfuture]

7 minutes ago, Me78569 said:

there is not nearly enough data to support that popping higher is a good idea.  

I carefully listened when you were experimenting with coding qwad and messing with pop, my outcome is great so far, thanks to you. That is of course if my 7x10 were truly popped to 320, I have no way of knowing, but the way they idle and have power when I need it seem to fit the description of what I hoped for. I only have about 5 thousand miles on them now and if had to guess, they probably already settled to 310 and hope they stay there for at least 100k

[Shainer]

1 minute ago, Me78569 said:

only some 2nd gen trucks report engine load correctly.  

 

 

As for bumping pop pressure PLEASE PLEASE PLEASE only do so if you want to mess with it, and you accept that it may not work or start when cold.  there is not nearly enough data to support that popping higher is a good idea.  

 

 

Listen you.  Come waltzing in with you voice of reason.  I'll have none of that!  400 bar is what I demand!!!!

Actually I'm calculating risks too.  I'm not so worried about cold, but I was contemplating what effect it would have on the IP.  Probably minimal, but what else would I do with my time if I didn't over analyze things.

[Mopar1973Man]

Just like @Me78569 mentions going above the 310 bar is totally experimental.

 

I've opted for the 320 bar. The stock injector pop pressure is 310 bar. I want a set of injectors that make 100k miles as the factory injectors did. I know that injectors settle after a period of time and the pop pressure falls off slightly in a short amount of mileage. I'm doing this for my own study work as well. So far ZERO starting issues cold. MPG has been OK but I'm not being fair because of recent activity that forced me to drive harder than normal. I will admit that my MPG offset is back down to the 140% I had set for the worn out 7 x 0.0085 injectors they only lasted 75k miles roughly. Flow is reduced with higher pop pressure, MPG is a bit better but hard to tell yet. I've still got that "purring lope" coming to stop which is totally harmless. 

 

2 minutes ago, Dieselfuture said:

they probably already settled to 310 and hope they stay there for at least 100k

That's exactly my thought on the 320 bar pop.

 

@pepsi71ocean reported that in about 28k miles his injectors were at about 280 bar which is below the 293 bar lower limit. I know he's reported that its clear up smoke and running better. He's running +100 HP.

 

As for some of the past post where guys jumped to 330 bar and higher then there was starting issues in the cold winter weather. 

[Me78569]

2 minutes ago, Shainer said:

Listen you.  Come waltzing in with you voice of reason.  I'll have none of that!  400 bar is what I demand!!!!

Actually I'm calculating risks too.  I'm not so worried about cold, but I was contemplating what effect it would have on the IP.  Probably minimal, but what else would I do with my time if I didn't over analyze things.

The IP doesn't give a hoot.  

 

For what it is worth the 7 x .012's at 330 were really nice.  Silky smooth idle, hugely reduced smoke for a given duration and mpg that most people wouldn't believe. 

 

 

...but it also wouldn't start below ~0*f

[Mopar1973Man]

@Shainer

 

280 bar = 4061.06 PSI

293 bar = 4249.61 PSI

300 bar = 4351.13 PSI

305 bar = 4423.65 PSI

310 bar = 4496.17 PSI

320 bar = 4641.21 PSI

 

Just raising the pressure at which the spray is delivered at. Once injectors starts to fall below 293 bar it starts to lose efficiency on the MPG side. Performance is still good for quite a ways but it starts to suffer below the 280 bar.

[Shainer]

59 minutes ago, Me78569 said:

The IP doesn't give a hoot.  

 

For what it is worth the 7 x .012's at 330 were really nice.  Silky smooth idle, hugely reduced smoke for a given duration and mpg that most people wouldn't believe. 

 

 

...but it also wouldn't start below ~0*f

You have a shop in the Springs or Denver to set these pressures?  I had one shop in the Denver area check a stock set.  Monkey and a football is the only way I could describe it.

[Me78569]

nope,

[pepsi71ocean]

23 hours ago, Mopar1973Man said:

 

@pepsi71ocean reported that in about 28k miles his injectors were at about 280 bar which is below the 293 bar lower limit. I know he's reported that its clear up smoke and running better. He's running +100 HP.

 

As for some of the past post where guys jumped to 330 bar and higher then there was starting issues in the cold winter weather. 

 

I will be pulling my Injectors around 40,000 miles and I will see. I'm hoping that going from 300 to 280 bar in  ~30,000 miles should be around 300 bad when I get that far. Which means I should get almost 50,000 before I hit 280 bar.

 

Smoke free with a smarty is the goal. And it works great. 

 

@Dieselfuture and @diesel4life I want to get a hold of you two and @Mopar1973Man about writing an article about pop pressure. So we can get something put together loosely for future use. I'm sure @Marcus2000monster would find it interesting as well.

Edited February 16, 2019 by pepsi71ocean

[Mopar1973Man]

I think some good gains can be had with ecomony and smoke control with added pop pressure. I will admit the flow rate is reduced I'm pretty sure of that.

[Dieselfuture]

No problem,  but I pretty much already said it all here lol.

[Ben]

On 2/13/2019 at 11:42 PM, Shainer said:

Question for the guys that have a Quad and suspected weak pop off pressures.  So here is my deal.  I have DAP 7x.095 aftermarket injectors.  I estimate I have maybe 100k miles on them.  Frankly I've been a little suspect of their performance from day one.  I noticed my idle RPM's have been trending upward.  Last few years I noticed idle hovering around 850.  I just took a look my idle RPM's over the past few days and now it settles in at around 870.  Any time I try to cruise at around 1000-1100 RPM I experience what might best be described as surging (manual trans with ceramic/kevlar clutch).  Life is busy so I just put up with it, except now it seems to be getting worse.  You know how it is, not bad enough to deal with... until it is.  So now I'm determined to improve this situation I was thinking about the low RPM cruise surge condition.  Get on my old forums and poke around, initially thinking it may be IP related.  Then I find this thread, and it got me thinking it could be one or more injectors are popping early causing uneven combustion spikes.  The 1000-1100 RPM range is kind of a resonant frequency for the condition.  Then I see you guys reporting on idle engine load.  Something I never paid any attention to.  The past few days when idle is sitting in that 870 range my engine load reports 0-5%.  1-4% being the norm.  I honestly would have figured that to be a normal range... but maybe it isn't?  Does what I describe sound like low pop pressure?  I performed a compression test a few years back.  Don't remember the numbers but do remember there was no more than a 5% deviation.  I think I have my injection timing cranked higher than I expected too.  Maybe capped at 20-21 degrees, not a hint of rattle.

Any thoughts are appreciated.  

 

 

You are not the only one. I was suspect from hour 2 after install. The idle says it all.

 

On 2/5/2019 at 4:41 AM, NIsaacs said:

 

Thanks for your experience, I am not into smoke/fuel going out the tail pipe. The RV's have been great so I will go back to them. I am totally happy with 400 hp, so far.....when a new turbo comes,  might get a small bug again

 

Thanks for the lesson, I really don't want drive around the smoke either. When you are loaded all the time it is a pain and even with 6 gears it causes delayed acceleration and now you need even more gears.

 

Is yours an HO model? 

 

You really need to wind out your shifts when hauling heavy. I used to regularly move equipment for my neighbor to job sites that consisted of a mini hoe and 10,000 lb skid steer on a gooseneck deck. 

 

Driving around the smoke is not a pain and not hard to do. You just have to pick your spots and rpms. Keep the rpm's UP!

 

Oh...and if you are an HO......you are no where near 400 with a wiretap and rv's. If you are an SO with a small input 6 speed then maybe upper mid 3's. Sorry.

 

I've been noticing the O'Reilly's/Autozone hp calculations thrown around quite a bit here with no actual back up. Not a dig against you. Just being realistic.

 

 

On 2/14/2019 at 4:14 PM, dripley said:

I see yall speaking of engine load while idling. My scan gauge shows 0% while idling. It has for quire some time. Is the scan gauge II the least bit accurate for that measure?

 

My Edge CTS 2 does the same as well. It makes no sense to me. Why would an engine show a load percentage similar to going down the road at idle? 

 

 

On 2/15/2019 at 8:10 PM, pepsi71ocean said:

 

I will be pulling my Injectors around 40,000 miles and I will see. I'm hoping that going from 300 to 280 bar in  ~30,000 miles should be around 300 bad when I get that far. Which means I should get almost 50,000 before I hit 280 bar.

 

Smoke free with a smarty is the goal. And it works great. 

 

@Dieselfuture and @diesel4life I want to get a hold of you two and @Mopar1973Man about writing an article about pop pressure. So we can get something put together loosely for future use. I'm sure @Marcus2000monster would find it interesting as well.

 

@pepsi71ocean

 

Man, I give you credit for hanging in there with the Smarty and an auto. Those 2 historically have gotten along like hot grease and skin. And I have only ever suggested the smarty to people with manual transmissions. 

 

A Smarty and manual is no issue. It is an absolute work around, no sweat. I drove a 400 horse at the wheels truck smarty and 150's smoke free for a long time. The truck was only a pill if I made it be that way. I could spiritedly shift through gears with minimal to no issues.  

 

The work around is eliminated with an auto. 

 

So..good on you. From an original MAD ECM guy...keep it up. 

Edited April 26, 2019 by Ben