Duramax Larger Injector Discussion
- Thread starter Blackbird1877
- Start date
Let's see if Pat's testing can narrow it down. Everybody is speculating what causes but it's yet to be proven. I'll go out on a limb & say it's a combination of all right now. The engineers had no idea what extremes these would be going to. Are we sure bent rods are not happening with stock power, towing heavy & just not getting as bad as with 550hp? We have no clue....yet. I may be waaay off base but I think if the only cause of bent rids was pressure,the piston would always go before the rods. Give it hell pat
they in no way corrolate/or are related to eachother. Its like saying a mag-hytek rear diff cover is going to lower your engine coolant temps.
EGT's crack pistons. My rods were not bent at all, and they have seen 2000* more times than I can remember. Yes, my pyro does go that high.
5x.024 is over 11 times larger than an LLY injector.
High RPM operation is the only reason I can see to use bigger injectors so far, and by high rpm, I mean more than 4000.
The reason for my myth is when a rods head up and cool down that much with 2,000 i would think over time that they would weekend. Then when have so much cylender pressure on a week rod thats what is bending them. But maybe i am not right i dont know
the 12v/24v run off P/T style pumps.
all diesel have to follow theis
M. mettering
A. atomization
P. pressuritaztion
I. injection
T. timing.
P/T in a 24/12v eninge are the onlythings that is really adjustable everything else is fixed. P, T, and injection amount are controled by the INJ pump and is variable... everything else is at the injector, thus why you put bigger INJ in to get more fuel.
CP3 everything is adjustable except atomiztion. that being the holes in the INJ tip them selves.
i belive i got that damn near on target...
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I'm using a Optrand Cylinder Pressure testing device that goes into the glow plug hole, and monitoring the information with various oscilloscope equipment. I just started playing with it after a year or so. I'm slow!
Jonathan (Fingers) is selling a commercial unit, but I'm not on the beta team for it, so I can't recommend it one way or the other. You can PM him here.
My experiences with large injector nozzles:
First off, if you're running one of the off the shelf programmers/chips/tuners/etc do not get big nozzles. You're wasting your time and money that could be spent elsewhere for some serious gains. Why is this? The Banks PDA, PPE, Quadzilla, Predator, Diablo, etc's of the world simply don't offer enough customization to make the nozzles worth it. You could easily just buy a bigger turbo and get more HP/$ that way. Afterall, that's pretty much what everyone here wants, the most efficient way to make your truck quick. Not only are they not efficient that way, they're dangerous. I ran 1700+ EGTs when doing boosted launches with nozzles and Banks 6 gun w/pda and no matter what variables I changed I couldn't get them down. With my current tuning by Mike I haven't had anything above 1400 period.
The biggest prerequisite for large injector nozzles from my experience would be that you already have EFI Live. The level of customization available as most of you guys know is mind boggling. Not only that, but for some stupid reason a lot of the guys that sell these nozzles treat them like they're freaking Confidential: Top Secret. What that means is that you, a paying customer, cannot even find out how much bigger your new nozzles are than your stock ones (I actually had this conversation with ATS). EFI then becomes the only way you can tell how much more your new nozzles flow versus the stock nozzles.
As with any good tune, it's all about the data. Is it harder to tune an engine with big injectors vs an engine with stock ones? I couldn't tell you, but Mike probably can. I'm still a horribly rank amateur newbie on EFI, and Mike is helping me out tons. I can tell you that I have about 25,000 miles on my 35% injectors (ATS Stage IV injectors) with no mechanical problems.
We're only on version 3 of my tune and we've eliminated the smoke at idle in park, we've eliminated the smoke in gear, and we've reduced the smoke up to 55% throttle position to a slight haze. When we started we were only getting about 20k psi rail pressure when we were demanding 2600, now we're sometimes slightly exceeding demanded pressures. I know pulse width has had a lot to do with it, but I couldn't tell you specifics as I just don't know enough about what I'm looking at yet. We've also just started messing with boost. Evidently my stock turbo was running itself up to 33 psi while the vanes were open.
Seat of the pants improvements are alot of fun as well. Like I said we're only on version 3 (we're only making one or two changes per version, and then logging the crap out of it), but I did a 4wd boosted launch IN 1ST GEAR launching at 2500+ rpms and 16+ psi of boost. I ended up chirping third gear on that launch.
I don't have anything conclusive to say that X is better than Y yet as far as what size injectors, and what changes do what, just because I'm too much of a noob. If Mike wants to, he's more than welcome to shed some light on here as to what exactly he's doing to it. All I can say is that it's a lot more fun to drive, both red-assing it and as a daily driver with 73,000 on her.
First off, if you're running one of the off the shelf programmers/chips/tuners/etc do not get big nozzles. You're wasting your time and money that could be spent elsewhere for some serious gains. Why is this? The Banks PDA, PPE, Quadzilla, Predator, Diablo, etc's of the world simply don't offer enough customization to make the nozzles worth it. You could easily just buy a bigger turbo and get more HP/$ that way. Afterall, that's pretty much what everyone here wants, the most efficient way to make your truck quick. Not only are they not efficient that way, they're dangerous. I ran 1700+ EGTs when doing boosted launches with nozzles and Banks 6 gun w/pda and no matter what variables I changed I couldn't get them down. With my current tuning by Mike I haven't had anything above 1400 period.
The biggest prerequisite for large injector nozzles from my experience would be that you already have EFI Live. The level of customization available as most of you guys know is mind boggling. Not only that, but for some stupid reason a lot of the guys that sell these nozzles treat them like they're freaking Confidential: Top Secret. What that means is that you, a paying customer, cannot even find out how much bigger your new nozzles are than your stock ones (I actually had this conversation with ATS). EFI then becomes the only way you can tell how much more your new nozzles flow versus the stock nozzles.
As with any good tune, it's all about the data. Is it harder to tune an engine with big injectors vs an engine with stock ones? I couldn't tell you, but Mike probably can. I'm still a horribly rank amateur newbie on EFI, and Mike is helping me out tons. I can tell you that I have about 25,000 miles on my 35% injectors (ATS Stage IV injectors) with no mechanical problems.
We're only on version 3 of my tune and we've eliminated the smoke at idle in park, we've eliminated the smoke in gear, and we've reduced the smoke up to 55% throttle position to a slight haze. When we started we were only getting about 20k psi rail pressure when we were demanding 2600, now we're sometimes slightly exceeding demanded pressures. I know pulse width has had a lot to do with it, but I couldn't tell you specifics as I just don't know enough about what I'm looking at yet. We've also just started messing with boost. Evidently my stock turbo was running itself up to 33 psi while the vanes were open.
Seat of the pants improvements are alot of fun as well. Like I said we're only on version 3 (we're only making one or two changes per version, and then logging the crap out of it), but I did a 4wd boosted launch IN 1ST GEAR launching at 2500+ rpms and 16+ psi of boost. I ended up chirping third gear on that launch.
I don't have anything conclusive to say that X is better than Y yet as far as what size injectors, and what changes do what, just because I'm too much of a noob. If Mike wants to, he's more than welcome to shed some light on here as to what exactly he's doing to it. All I can say is that it's a lot more fun to drive, both red-assing it and as a daily driver with 73,000 on her.
I was just trying to get a discussion statred on this topic. I was not planning on putting them in my truck(yet) My current wish list is as follows.
1.EFI Live
2.4088
1.EFI Live
2.4088
I hope this is true for my sake as im now at 38,000 miles in 10 months with 20,000 miles at or over the 500 rwhp mark. To me better atomization seems like the way to go over more volume. i would think tht a smaller injector would provide a better and more precise pattern then bigger injectors. just my thuoughts.
I still say big or bigger injectors is the way to go. I have explained my reasoning, right or wrong in past threads. All I can say is they work for me.
I do appreciate the theories expressed here. Very interesting.
I do appreciate the theories expressed here. Very interesting.
X2, I also agree with your theory Steve. I belive that the extra fuel will help in cooling the egts
I am right there with you Steve. I have 80% overs in my 02 for the same reason.
I would like to note that mine comes up on RPM violently withe the 50%'s installed. I hade the engine apart for injector failure and decided, what the hell and sent the tips to ExtrudeHone and im happy i did! Now i need more air to makem work! really woke the truck up!
Dunno. 800 horses can't be wrong.
but honestly pat, I don't think you can say that more can't be achieved with bigger ones in your application without trying them... the MDEs don't count, too many others had trouble with them as well.
Not saying you will but to continuously say the stockers are good enough is a bit much when you don't really know if bigger ones may make more or make the same amount while being easier on parts....
whatcha think???
