This thread is for the results of the testing of the differnece pop pressure at the same size.   

 

ANY REPLIES NOT ON TOPIC AND OR WITHOUT DATA WILL BE DELETED.  

 

I will be running 3 sets of DAP injectors first set at 305 bar, next at 330 and the last at 350 bar.  We are going to compare real world situtations and what the pros and cons are of increasing pop pressure.   All tests will be datalogged and video taped if applicable.   

 

The tune will be EXACTLY the same for all injectors.  al runs done on Lvl 3, so no wiretap being used

 

Quote

Timing Parameters
Fuel Load Timing	3
Low PSI Timing Reduct	5
Timing Reduct Scaling	50
LightThrottle Timing Adv	1.5
Light Throttle Limit	30
Timing Equilzer
1500RPM	17
2000RPM	20
2500RPM	23
3000RPM	28
MAX	30
Boost Level Fueling - CAN Bus
0 PSI	66
1 PSI	66
2 PSI	67
3 PSI	68
4 PSI	70
5 PSI	71
6 PSI	72
7 PSI	74
8 PSI	76
9 PSI	78
10 PSI	80
11 PSI	82
12 PSI	84
13 PSI	86
14 PSI	90
15 PSI	94
16 PSI	98
18 PSI	102
20 PSI	106
22 PSI	110
24 PSI	114
26 PSI	118
28 PSI	120
30+ PSI	120

 

 

Test conditions. 

 

Quote

 

 

1. 0-60 WOT take off, same stretch of road

2. 55 mph egt on same stretch of road showing egt

3. Lugged 45 mph locked od pull to compare spool.  

 

 

 

 

305 BAR

Test 1 0-60 WOT take off, same stretch of road

 

 

 

 

Test 2 55 mph egt on same stretch of road showing egt

 

 

Test 3 Lugged 45 mph locked od pull to compare spool.  

 

 

 

 

 

330 BAR

Test 1 0-60 WOT take off, same stretch of road

 

 

Test 2 55 mph egt on same stretch of road showing egt

 

Canbus fueling is ~1125 and egt right around 710-725*f  ( road is slightly uphill

 

 

Test 3 Lugged 45 mph locked od pull to compare spool.  

 

 

350 BAR

 

Test 1 0-60 WOT take off, same stretch of road

 

 

 

 

Test 2 55 mph egt on same stretch of road showing egt

 

 

Test 3 Lugged 45 mph locked od pull to compare spool.  

Edited February 12, 20187 yr by Me78569

This morning was the first cold, 7*f, morning with the stock bar injectors.  I can say that the 330 bar injectors started WAY easier, the truck was about as angry as I have seen it this morning.   The 7 x .009's acted about the same at -30*f.

 

injectors are back off to DAP to get repoped from 330 to 350 bar.   

10 minutes ago, Me78569 said:

This morning was the first cold, 7*f, morning with the stock bar injectors.  I can say that the 330 bar injectors started WAY easier, the truck was about as angry as I have seen it this morning.   The 7 x .009's acted about the same at -30*f.

 

injectors are back off to DAP to get repoped from 330 to 350 bar.   

 

That being said, what pop pressure range would you suggest for my 7 x 0.0085 +75 HP injectors? This spring when I can swap over to the 1996 Dodge Ram 1500 I want to jump into this higher pop pressure I'm betting it will also improve economy as well with better atomization. 

My theory is as injector size goes up pop pressure can be increased without neg results by more and more.  

 

7 x .0085 I doubt you would gain anything honestly.  I dont think I would personally mess with pop pressure if I was you.  

 

If we say that 7 x .012's like 330 bar ( still hard to say that)  and stock 7 x .007's are at 305 ish, then do a fuzzy math increase then you are looking at 310 bar or something for 7 x .0085 

Remember stock injectors are 310 Bar. I think I'm at 300 bar now on the 7 x 0.0085 now. 

 

lolol 250 psi is 17 bar.  bosch says that 310+17 is within spec.... so I guess 327 is the limit lolol

Id put them at 315 bar then

This comes back to your 330 bar setup that you seem to like so much. Makes sense now. Being starting quality is good and smoke reduction is good too.

4 hours ago, Carbur8tr said:

which is partially why no one has come forward and said that they could audibly hear a change in timing.  I know for me I honestly heard no difference and I suspect that there was not.

 

I had mentioned when I first went to 365 bar that it sounded like my idle got a little noisier, a slightly more pronounced rattle. If you've ever heard an injector on a pop tester this makes sense. Pop any given injector at 280 bar, and then 365 bar, and they definitely sound different.

Edited January 16, 20187 yr by kzimmer
Spelling

I reran the idle test with the stock bar injectors, I wasn't happy about the 120*f+ difference in egt in the logs it was too much to be correct.  this time the average egt was ~50*f more with 305 bar vs 330 bar, which is much more acceptible. weird thing is we see that 50*f difference in multiple steady state tests.   Rest of the stats are nearly the same.  Results are nearly the same. Conclusions are the same when I compare the 2 sets of injectors.

Edited January 16, 20187 yr by Me78569

I've personally noticed a very large fluctuation of EGT's during idling this winter. Nothing recorded. But with different combinations of ambient temp (and subsequent IAT), and ECT, I've seen it float around quite a bit. Not saying this is the case 100% for you, but it makes sense that it could be a little inconsistent.

 guess I need to get busy @dieselautopower Can you comfirm that these injectors are the same nozzles as I was running before at 330 bar?  IE your guys just repopped what I sent back at 350 bar.

Edited January 27, 20187 yr by Me78569

1 hour ago, Me78569 said:

 guess I need to get busy @dieselautopower Can you comfirm that these injectors are the same nozzles as I was running before at 330 bar?  IE your guys just repopped what I sent back at 350 bar.

 

 

 

 

Please check the yellow sticker in the upper right corner.  Pressure is written in pen over the build date.   If you have more questions please let me know.

13 minutes ago, dieselautopower said:

 

 

 

 

Please check the yellow sticker in the upper right corner.  Pressure is written in pen over the build date.   If you have more questions please let me know.

yep it is,  sorry I wasn't clear are these the same physical injectors as the 330 bar setup, just repopped to 350(per the sticker)?   I hope they are because that allows me to compare pop without possible minor difference in the nozzle.

That's a good point Me.

1 hour ago, Me78569 said:

yep it is,  sorry I wasn't clear are these the same physical injectors as the 330 bar setup, just repopped to 350(per the sticker)?   I hope they are because that allows me to compare pop without possible minor difference in the nozzle.

 

 

Is there any soot on the tip of the nozzle?  The flow should be the same even if they are new ones.  Flow is within 1% on the nozzles.

 

They are used but clean.  Easy to see via discoloration on the tip.  

 

Good to know on flow.  We will see what I find

Cool!  We polish up the shank on the nozzle but only clean the tips/holes very lightly.

 

should be +/- 0.03 lpm per set so thats only about 1-2% spread in flow across the set.

350 bar injectors are in an WOW is all I can say.  When comparing the 305 bar to 350 bar I could EASILY run a tune starting %5 higher with the 350 bar injectors and still have significantly less smoke.  

Updating the first post now.  

The 0-60 run of the 350 bar is up.  And they are squeaky clean, however as @jlbayeswas guessing the resulting 0-60 time is ~.5 seconds slower.    However I am ok with that, I think these injectors will settle down to ~340 bar in a few weeks and it will be about right. 

 

You will also note that EGT's are higher with the 350 bar, which is what @kzimmer found as well.   Looking at boost I might wanna check for a boost leak I guess haha.  I'll do that this week at some point and rerun the test if I find any.  However if we look at the idle stuff below you can see the loss in fueling as a result of higher pop.

 

I will say there is a defined lul right off idle now. 

 

 

 

Next is the idle compare, ignore the difference section I did not recreate it. 350 bar = green330 = white and 305 = orange. 

 

-Again here I see about a %5 lose in fueling if we compare fueling commands at idle from the 350 bar vs the 330 bar 
-EGT's are up as well. 

-note the ave/min/max section showing a significantly worse idle than the 330 bar.

 

Edited February 5, 20187 yr by Me78569

Good work Nick!  Would like to verify there is not a boost leak.  After a few more days of running them and some MPG charting I will ask you what pressure you prefer and for what purpose/application.  

 

AWESOME write up!

Very interesting. There seems to be a plateau that occurs somewhere between 330 and 350 bar. A lot of this info jives with mine. I never recorded idle state rpm in gear like you did, but I saw the same thing with the naked eye.