LB7: SAC-style Injector Life

DAVe3283

Heavy & Slow
Sep 3, 2009
3,327
13
38
33
Boise, ID, USA
ReaperLegion.net
This thread will be a long-term review of the SAC-style +75% injectors I put in my truck, and how they hold up.

Backstory
As described in my [THREAD=70438]other thread[/THREAD], I had a set of +100% injectors take a giant crap 9,351 miles after Exergy had given them a clean bill of health.
[YOUTUBE]cKWdxVv66tI[/YOUTUBE]
So, I eventually decided to try out the new SAC-style tips, and step down to a +75% injector. Brent @ Lincoln Diesel Specialties hooked me up with a set for a great price, and I swapped them in. They came with a basic flow sheet from S&S, and while it wasn't as comprehensive as Exergy's flow sheet, it had the basics.

Here is the old set, vs. the new set from LDS:
DSC_0253.jpgDSC_0254.jpg
Those are legit new bodies, not cores. The manufacturing date on the bodies was from January 2016, and this was in March.

So, WTF happened to this injector?
DSC_0255.jpg
It looks like it caught fire!?! I thought I might have lifted it, but there was no blowby, and the o-ring at the top of the injector was in tact (though slightly crispy). As a side note, 2 the old injectors had tons of raw diesel in the cups, almost like the tips weren't on tight? No visible diesel in the oil (waiting on analysis results to confirm this), though.

Got it all buttoned up:
DSC_0257.jpg

Boy, what a difference! Immediately all my idle smoke was gone. I have 16.5:1 compression and a cam with a lot of overlap, so I still get a tiny bit of haze at elevation, but you have to look for it, and catch it in the right light.

Not only was the idle smoke gone, but it is easier to get on top of the turbo, and with less smoke. It also makes more power (by track MPH) than the old set, on the same tune. Which is impressive, because these injectors are smaller...

Day 0
Hours on injectors: 0
Miles on injectors: 0
Miles on motor: 10,796
Miles on truck: 307,032
Code:
           Drive  Park
BALRCYL1   -2.69  -2.77
BALRCYL2   +1.96  +1.80
BALRCYL3   -0.96  -0.93
BALRCYL4   +0.39  +0.39
BALRCYL5   +0.03  +0.08
BALRCYL6   +0.13  +0.54
BALRCYL7   +0.27  +0.53
BALRCYL8   +0.72  +0.45
MAINRATE 12.3mm3 5.9mm3
These are the best balance rates I have ever seen on this motor, so I am not concerned about Cyl#1 being over 2 in park. And with +75% sticks, "only" 6mm3 in park at hot idle seems reasonable to me as well. Mainly, I just want to track the balance rates over time.

Day 17 (today)
Hours on injectors: 28.0
Miles on injectors: 1,138
Miles on motor: 11,934
Miles on truck: 308,170+

Having put a few tanks through the injectors, it appears I get slightly better mileage than with the old injectors, despite driving with a heavier foot. I'll keep logging the mileage and see what it does when I settle back into a routine so I can get a fair comparison. But so far, I am extremely pleased with the injectors.

I'll come back and post periodic updates to see how these injectors hold up. Hopefully the SAC-style tips last as well on the LB7 as they do on the LLY+!
 

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Awenta

Active member
Sep 28, 2014
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Awesome man thank you. Looking forward to see how it goes. I'm also doing SAC style injectors soon.

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motoking_1990

New member
May 8, 2011
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Terre Haute, IN
Subd I'm still curious how exergy passed them and they got like that! How many miles on the old? I will go back and read the other thread it may fill me in better.

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DAVe3283

Heavy & Slow
Sep 3, 2009
3,327
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Boise, ID, USA
ReaperLegion.net
I bought the injectors used from a guy who said they only had a few sled pulls on them, and he went to something bigger. I built my motor, and ran them for 1,445 miles, then had to tear my SoCal heads off because [THREAD=63518]one of them cracked[/THREAD]. Even with that few miles on the injectors, I was suspecting some of my tuning issues was actually injector issues, so I sent them off to Exergy to get checked and balanced. That cost me $1,490.00 I should have just put toward the new set to begin with, but live and learn. Anyway, they came back with a clean bill of health and a balance sheet, so I threw it all back together, and it seemed to run better (but that was probably just because the head wasn't cracked anymore). 9,351 miles and 10 months later, well, you saw the video.
 

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THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
3,791
3
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39
ZEPHYRHILLS, FL
Those appear to be a micro SAC style nozzle judging from the actual protrusion, but would have to see inside to be certain. The SAC style nozzle has a different style flow rate to it from what I read on them where they actually flow less at idle areas under lower pressure, but as pressure goes up, so does the flow. When I read on it, there was alot of chnages that came into play when changing nozzle type. When mine go, I will be swapping over to SAC types as well.
 

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
13,375
21
38
Mid Michigan
Thanks Dave. As usual, I'll look forward to your continued reports.

BTW, GO BLUE! :hehe: We Arrival/Marine Blue guys have to stick together!
 

x MadMAX DIESEL

<<<< No Horsepower
Dec 30, 2008
7,520
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Lexington, Ky
I bought the injectors used from a guy who said they only had a few sled pulls on them, and he went to something bigger. I built my motor, and ran them for 1,445 miles, then had to tear my SoCal heads off because [THREAD=63518]one of them cracked[/THREAD]. Even with that few miles on the injectors, I was suspecting some of my tuning issues was actually injector issues, so I sent them off to Exergy to get checked and balanced. That cost me $1,490.00 I should have just put toward the new set to begin with, but live and learn. Anyway, they came back with a clean bill of health and a balance sheet, so I threw it all back together, and it seemed to run better (but that was probably just because the head wasn't cracked anymore). 9,351 miles and 10 months later, well, you saw the video.


Did they sat they had meta fragments in them?? That's the story lately with 3 onjector sets they've had in past few moths from people including myself. I find that odd
 

DAVe3283

Heavy & Slow
Sep 3, 2009
3,327
13
38
33
Boise, ID, USA
ReaperLegion.net
Those appear to be a micro SAC style nozzle judging from the actual protrusion, but would have to see inside to be certain. The SAC style nozzle has a different style flow rate to it from what I read on them where they actually flow less at idle areas under lower pressure, but as pressure goes up, so does the flow. When I read on it, there was alot of chnages that came into play when changing nozzle type. When mine go, I will be swapping over to SAC types as well.
I didn't really have to mess with the tuning at idle to get it to run right. It is basically a stock tune until 1000 RPM. I might play with the pilot timing later, see if I can quiet down the motor a bit, but these injectors are already way quieter than the previous set.

Thanks Dave. As usual, I'll look forward to your continued reports.

BTW, GO BLUE! :hehe: We Arrival/Marine Blue guys have to stick together!
'Tis the best color! :hug: And I'm still rocking your cabin air filter retrofit kit. Just stuck new filters in, amazing how much crap gets caught in the filters.

Did they sat they had meta fragments in them?? That's the story lately with 3 onjector sets they've had in past few moths from people including myself. I find that odd
No, they said they were fine. Or more accurately, they didn't say they found anything wrong, just said that they balanced up just fine. I am not sure what to make of the quick failure. I suspect they were marginal when I bought them (which is why I sent them out after only 1000 miles), and it seems I was right, even if Exergy didn't find the problem. I still have them, but I don't know what I am looking for if I were to take them apart, so who knows what really went wrong. And no way am I paying another $1k+ to find out :eek:
 

DURAMXD

BOB SAGET!
Apr 24, 2012
348
0
0
Wichita, KS
Definitely following this. Debating on going with the SAC style LB7 injectors when I go bigger or just doing an LLY top end swap on my RCSB.
 

yellowchevy

Active member
Sep 9, 2010
1,828
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36
Louisburg, KS for now
Glad you got your smoke figured out David. I know we talked about it on the phone alot when discussing turbos so I'm glad you're alot happier!!

Hows that 366? Working better with good injectors?

Yellowchevy
 

DAVe3283

Heavy & Slow
Sep 3, 2009
3,327
13
38
33
Boise, ID, USA
ReaperLegion.net
Glad you got your smoke figured out David. I know we talked about it on the phone alot when discussing turbos so I'm glad you're alot happier!!

Hows that 366? Working better with good injectors?

Yellowchevy
The S366 did help the bottom end, as we discussed. I ended up sticking the billet 71mm compressor and cover on the S366 center section and had a local shop balance it. So now I have a S371 again, but with the 360 thrust washer. With the new injectors, the S371 comes up as well as the 66 did, but flows better up top.

I'm pretty happy with the setup now. Heading out to the strip again on Sunday, actually, to give a coworker's Mustang a hard time. :D

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