seems like you're on the right track. Honestly (purely assumption) the only thing thing I see possibly having a shortened life would be the injectors... And to me on these trucks you spend $600(+/-) on good injectors that should last a couple hundred thousand miles as can be changed in 2hr with basic hand tools.. Even if life was shortened 25%,that isn't an end all imo. So far our results have been positive and like you I'm excited to see what we come up with. Honestly if it doesn't gain much, then at least this question can be paid to rest with actual real world results!
Vp44 Injector Pop Pressure theory and testing
- Thread starter me78569
- Start date
I believe the reason for this thread was to get peoples thoughts, ideas, criticisms and providing data to all. I think that we all appreciate your ideas and your criticism. It helps us to look and think about things that maybe we hadn't or to test and try things that would help prove or disprove benefits. It just seems that every few comments you just repeat the same old "it's a waste of time" comments.. If it turns out we prove it not beneficial it's no sweat off my back, and I'm guessing the others doing it won't mind either. It is an experiment. Simply trying to make a good thing better.. Not a big deal either way. Again thanks for your thoughts..
at 330 bar I don't see issues with lifespan, it's 3 bar over what bosch says it ok. Doesn't worry me. I see no reason to say the vp is being hurt, the seat of the injector it is reasonable to say lifespan will be shortened. Considering stockers often last ~200,000 miles I would say even if lifespan is reduced by %50 it is still reliable. Nozle quality comes into question here, but we are stuck arguing something that is beyond what most can test for.
To date I have not had any observable ( keyword) downfall to the 330 bar. Improvements appear to be up for debate and I already posted the logs so I wont beat a dead horse.
dieselbeef
dick doggin
and that's what I give ya....
I am starting to get some info on 350 bar. The 330 bar injectors were repopped to 350 bar, so same nozzle.
It looks like 350 bar is to high for most applications. Like the smart guys said haha.
Negs
- idle state is less smooth than stock bar and 330 bar. 330 bar is smoothest 305 bar 2nd smoothest.
- EGT is up at idle and at cruise state, again 330 bar is lowest. 305 vs 350 is pretty much the same.
- boost is done, 0-60 times are up at 350 bar. 305 vs 330 bar are nominal difference. The idle state logging shows an average of %5 more duration needed to keep steady rpms wiht 350 bar vs 330 bar. So we can assume the difference is ~ that.
- stalling when going into gear seems possible now. Hasn't happened yet, but it hasn't been near 0* f since installing the injectors. Rpms do fall a good bit lower than 305 or 330 bar.
Pro
- Smoke output is WAY down across the board with 350 bar. in order to make smoke output equal to 305 bar the tune starting % needs to be increased by ~%10.
- Starting is better than 305 bar and about the same as 330 bar.
I haven't done the lugged pull test yet, but I am pretty sure the 350 bar are a touch worse than 330 bar, but better than the 305 bar.things are busy right now so it might be a few days until I can get around to fixing my lockup switch.
take what you want from it, like always. I am going to keep the 350 bar, mostly because I am not wanting to swap injectors again, but also I like how clean they run.
It looks like 350 bar is to high for most applications. Like the smart guys said haha.
Negs
- idle state is less smooth than stock bar and 330 bar. 330 bar is smoothest 305 bar 2nd smoothest.
- EGT is up at idle and at cruise state, again 330 bar is lowest. 305 vs 350 is pretty much the same.
- boost is done, 0-60 times are up at 350 bar. 305 vs 330 bar are nominal difference. The idle state logging shows an average of %5 more duration needed to keep steady rpms wiht 350 bar vs 330 bar. So we can assume the difference is ~ that.
- stalling when going into gear seems possible now. Hasn't happened yet, but it hasn't been near 0* f since installing the injectors. Rpms do fall a good bit lower than 305 or 330 bar.
Pro
- Smoke output is WAY down across the board with 350 bar. in order to make smoke output equal to 305 bar the tune starting % needs to be increased by ~%10.
- Starting is better than 305 bar and about the same as 330 bar.
I haven't done the lugged pull test yet, but I am pretty sure the 350 bar are a touch worse than 330 bar, but better than the 305 bar.things are busy right now so it might be a few days until I can get around to fixing my lockup switch.
take what you want from it, like always. I am going to keep the 350 bar, mostly because I am not wanting to swap injectors again, but also I like how clean they run.
dieselbeef
dick doggin
how much higher is the egt..cuz on my truck..i watch that gauge more than I watch the road
~50*f at cruise when comparing to 330 bar, but about the same as 305 bar
~70*f hotter at WOT than 330 and 305 bar.
~20*f hotter at idle in gear, comparing to 305 bar after ~1 minute of idle, 330 being lowest 305 being 2nd and 350 being hottest.
However none of the injectors gave me any EGT issues. it is hard to break 1200 while towing, EGT's don't hit 1300*F until I am flogging it above 2400 rpm where the vgt is starting to get out of it's map and the vanes are opening.
why do you have egt issues? Trouble getting on top of the turbo?
~70*f hotter at WOT than 330 and 305 bar.
~20*f hotter at idle in gear, comparing to 305 bar after ~1 minute of idle, 330 being lowest 305 being 2nd and 350 being hottest.
However none of the injectors gave me any EGT issues. it is hard to break 1200 while towing, EGT's don't hit 1300*F until I am flogging it above 2400 rpm where the vgt is starting to get out of it's map and the vanes are opening.
why do you have egt issues? Trouble getting on top of the turbo?
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Big Blue24
Comp Diesel Sponsor
I used to love doing on-road testing years ago playing with different injectors, pop pressure settings, static timing settings, etc.
So keep up the tinkering, it's a great way to learn your truck inside and out!
One thing that is tough for performance companies is traditionally, paying customers were looking for more performance/power per $$$ spent. If higher pop pressure took away 25 peak HP, that has traditionally been discouraged even if it helped with off-idle throttle response.
Have you been testing fuel economy with your pop pressure changes, has it changed? Anything to add fuel economy seems to be a common question that gets phoned in once or twice a week.
So keep up the tinkering, it's a great way to learn your truck inside and out!
One thing that is tough for performance companies is traditionally, paying customers were looking for more performance/power per $$$ spent. If higher pop pressure took away 25 peak HP, that has traditionally been discouraged even if it helped with off-idle throttle response.
Have you been testing fuel economy with your pop pressure changes, has it changed? Anything to add fuel economy seems to be a common question that gets phoned in once or twice a week.
I agree %100 people typically want cheapest $$ / HP when talking about injectors. No harm there.
I have not gotten steady enough data on mpg to say one way or another. my hunch is that 330 did best on mpg and 350 and 305 were about the same. If I look at cruise state egt's the 330 bar seemed to cruise a good bit cooler than the 305 and 350 bar did / do. however I am in no way going to say 330 bar is the magic number for hyper miling.
Overall I even think the amount of pop increase that can be done before issues arise depends on the the size of the injector. I am guessing that a bigger set of injectors, says 7 x .012, is less prone to issues related to pop than a set of 7 x .009's or similar.
I would guess it is a moving number as to what pop can be set at before issues come up. this is yet another reason why builders dont like the idea. It requires much more time to fine tune each set, and the cost to produce goes through the roof.
mostly I just find it fun and interesting to mess with.
I have not gotten steady enough data on mpg to say one way or another. my hunch is that 330 did best on mpg and 350 and 305 were about the same. If I look at cruise state egt's the 330 bar seemed to cruise a good bit cooler than the 305 and 350 bar did / do. however I am in no way going to say 330 bar is the magic number for hyper miling.
Overall I even think the amount of pop increase that can be done before issues arise depends on the the size of the injector. I am guessing that a bigger set of injectors, says 7 x .012, is less prone to issues related to pop than a set of 7 x .009's or similar.
I would guess it is a moving number as to what pop can be set at before issues come up. this is yet another reason why builders dont like the idea. It requires much more time to fine tune each set, and the cost to produce goes through the roof.
mostly I just find it fun and interesting to mess with.
Smokem
Turbler
I'm going to start by saying that street size injectors are not my main focus, nor the majority of what I do, but I have seen a surge in people contacting me regarding this. And based on what I repeatedly hear, it seems the overwhelming solution to idle haze, roughness, and poor efficiency would be to not use a set $150 Chinese nozzles.
Feel free to debate any ideas or "solutions" you deem plausible, but from my extensive experience there is no short cut that yields the same result as using quality components.
Feel free to debate any ideas or "solutions" you deem plausible, but from my extensive experience there is no short cut that yields the same result as using quality components.
And to be %100 clear I have not told anyone that increased pop was the way to go. I have had numerous people ask me what my thoughts are.
What I say is.
" I like to mess with stuff, I dont know the long term effects etc Dont go down this road unless you want to figure it out for yourself. this is not a cure all of issues related to poor quality injectors"
I completely agree that there is no replacement for quality overall. I am half way sorry I posted this over here, but it went from a "what happens" to a " why is it not worth it" arguement. I dont care about the argument of why or why not, just curious as to the result of the change.
However it seems that the diesel community is a lot less of people asking " why" and more so people following "trends" That's not how I think.
What I say is.
" I like to mess with stuff, I dont know the long term effects etc Dont go down this road unless you want to figure it out for yourself. this is not a cure all of issues related to poor quality injectors"
I completely agree that there is no replacement for quality overall. I am half way sorry I posted this over here, but it went from a "what happens" to a " why is it not worth it" arguement. I dont care about the argument of why or why not, just curious as to the result of the change.
However it seems that the diesel community is a lot less of people asking " why" and more so people following "trends" That's not how I think.
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Another Neg to add to 350 bar that I did not have at 330 bar.
Cold starting, when temps get down to ~15*f the truck becomes VERY hard to start. 330 bar started considerablly easier than 305 bar when cold.
I think the issues with 350 bar is lack of timing while cranking. the effect of the increased pop pressure should, in theory, be greatest as rpms drop.
I need to wire up a rheostat and fool the ecm into thinking it is VERY cold to try and over advance timing at cranking. ( if the ecm even controls cranking timing, I have a theory that it doesn't)
dunno this is a pretty big issue for my situtation, it will start, its just not happy about it. Almost like a light switch, above 20*f and it pops off just fine, below 15*f and boy does she smoke.
Cold starting, when temps get down to ~15*f the truck becomes VERY hard to start. 330 bar started considerablly easier than 305 bar when cold.
I think the issues with 350 bar is lack of timing while cranking. the effect of the increased pop pressure should, in theory, be greatest as rpms drop.
I need to wire up a rheostat and fool the ecm into thinking it is VERY cold to try and over advance timing at cranking. ( if the ecm even controls cranking timing, I have a theory that it doesn't)
dunno this is a pretty big issue for my situtation, it will start, its just not happy about it. Almost like a light switch, above 20*f and it pops off just fine, below 15*f and boy does she smoke.
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