LB7: SAC-style Injector Life

vtecjj

New member
Jul 22, 2011
1
0
0
LB7 Resurrection

Supd...Interested in SAC45's
My LB7 died April of 2017. I stayed on a bad (2nd set) of oem injectors for OVER A YEAR. Smoked like crazy, bad idle, bad mileage. When the oem injectors completely went out, I began to get a fuel knock...and drove almost 300miles back home! Suffice to say, I melted one glow plug tip (#6 cyl) and cracked that piston.

Fast forward to December (and several $$$ later) and I got another LB7 from a wrecking yard with 154K miles and have the following to install and tune:

Head Studs
Refreshened Heads
SAC 45's
LBZ CP3
AFE DFS 780
CAT Filter adapter @Filter Head
PPE: Up Pipes, Downpipe, Manifolds
HTT ProMax 64 Drop In Charger
EFI Live

(Tranny build coming in 2018)

A mechanic was hard pressed to stay with NEW OEM injectors, especially with filtration. But I decided to go with the SAC's instead.

Hope I made the right choice :confused:

This thread helps a lot! Any updates? Thanks!
 

DAVe3283

Heavy & Slow
Sep 3, 2009
3,681
236
63
Boise, ID, USA
Mine is still running great, though the truck is doing more short trips lately, and not racking up the miles like before. I'll update the full set of data next spring sometime. For now, my subjective opinion is the SAC injectors are still doing great. I still recommend them over the stock injectors.

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Brent@LDS

Vendor
Vendor/Sponsor
Aug 23, 2011
651
1
18
Wisconsin
We have sold a ton of the SAC45 injectors with all positive feedback and great results! We highly recommend them to our customers if they can afford them.
 

dirty_maxxbob

New member
Jan 19, 2015
24
2
3
ca
I have Exergy 45% SAC’s and mine are doing great even with the shity CA diesel. I have over 50k miles on mine. They are pretty quiet and are much more responsive then non SAC injectors. I put these in December of 2015 Since I cracked 2 stock injectors and Lenrenzo over at SoCal diesel swore up and down on these and now I know why. I have a FASS 150 and a Cat fuel filter in place of the stock fuel filter on the head. I try to clean my injectors every 6 months and the filters get changed every 15k miles. I use my truck to tow over weight studio trailers that are well over 15,000 pounds. I recently changed the filters and these where the balance rates on the edge, I know it’s not a tech 2 but something is better then nothing if anyone has questions or is considering buying these and is hesitant feel free to PM me.

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fl0w3n

Active member
Jan 8, 2015
508
25
28
Why do you say California diesel is shitty?


Also, at this point, has anyone heard of failing SAC style injectors?
 

outtatimexx

New member
Aug 21, 2017
21
0
1
Perry, Ga.
Sac-Style injectors

Ok, I am almost sold on the sac injectors, but I have one more question before I pull the trigger on a set. I have been running stocks in my '02 cc Duramax for 10 years, and always felt I needed to add something to the fuel, I mean every tankful. Can I expect to be able to slow down on the cleaners, lubricants I have been adding all along? Or is it best to continue to add lubricants to every tank? I realize the LB7's were built before ULSD, Just wondering? Anybody have an idea?
 

DAVe3283

Heavy & Slow
Sep 3, 2009
3,681
236
63
Boise, ID, USA
I don't run any additives anymore, and haven't noticed any issues.

On the stock CP3 and injectors I would always run something, either Stanadyne or ashless two stroke oil. Since the build, no additives and no problems.

It shouldn't hurt anything to continue running a high quality additive, though.

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Brent@LDS

Vendor
Vendor/Sponsor
Aug 23, 2011
651
1
18
Wisconsin
We have not seem any shorter life expectancy on the SAC injectors nor stock with people not running additives. Sure doesn't hurt to run some from time to time but its not mandatory.
 

THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
3,890
43
48
43
ZEPHYRHILLS, FL
I ran ALL the additives and my stock ones still went at 70K miles. The set that was in it when I got it had 125K miles on them and never had additives run through them, and were still in ok shape. So with the SAC's I figure I'll just run biocide since it sits for long periods of time, and call it a day.
 

Blujett2.0

New member
Sep 14, 2018
4
0
1
Niverville, MB
We have not seem any shorter life expectancy on the SAC injectors nor stock with people not running additives. Sure doesn't hurt to run some from time to time but its not mandatory.

Hello guys! Thanks for the great info in this forum. I'm flying out next week to bring home a 2001 Duramax ecsb with 62K miles on it. Reading up on the injector issues is starting to give me cold feet. Has the SAC-style injectors solved the constant failures of the VCO nozzle types? Have there been any failures with the SAC type Brent@LDS? I could use all the help I can get! Thanks!
 

Brent@LDS

Vendor
Vendor/Sponsor
Aug 23, 2011
651
1
18
Wisconsin
We have not seen any of the SAC 45 injectors fail since they come out in 2013 and have sold a ton of them! If and when you need injectors for your LB7 they are the way to go!
 

oldred95

New member
Mar 17, 2013
10
1
3
Its my turn to get on board the SAC 45 band wagon. Just shy of 50,000 miles on stock reman injectors and it finally started smoking on a consistent basis. The balance rates were very meh but two cylinders in particular were both in the 7s at idle in park but I forget which two. I got SAC 45 tips from LDS and finished up the install today. My base tune was inspired by THEFERMANATOR's findings. Right off the bat I noticed the strong fuel odor was gone and it was idling smoother and very very quiet. I would say borderline LBZ quiet but with a different exhaust note and overall tone to the engine. I did set my valves while I was in there but they were only off a couple thousandths if that. My balance rates are now at or below + or - 1 on all cylinders but cylinder #6 which is at 1.8. I'm going to continue to fiddle with the timing and see if I can't bring it in a little closer yet though. It runs so smooth and has an endless pull and turbo lag is a thing of the past. I love how I can roll into the throttle in 5th, converter locked at 1200-1300 and there is no lag. No fuel rattle and slow to build boost like before, the turbo spools and it gets up and runs. The only thing I have noticed unusual but probably normal is how loud the engine gets when the pilot injection shuts off at 2600-2700 rpm. It literally goes from being as quiet as a LBZ to sounding like a 7.3 power stroke. I understand that the pilot injection turning off can have that effect but its the exact opposite effect it had with the worn VCO injectors. It was noisy all the time until the pilot shut off then it got quiet especially when under boost. Has anyone else noticed this?
 

DAVe3283

Heavy & Slow
Sep 3, 2009
3,681
236
63
Boise, ID, USA
I've got +75% SACs in my truck, and it doesn't get noticably louder when the pilot shuts off. I did tweak exactly where pilot turns off, but not much.

You may be turning the pilot off at too low of a mm3 value. If this is happening at full throttle or close to it, you might have too much timing for your pulsewidth or boost level.

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THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
3,890
43
48
43
ZEPHYRHILLS, FL
Mine doesn't get loud when pilit shuts off, if anything it just sounds MEANER. My converter choice may have some say in that as I got a 1800 stall when I did mine, so 2700 is normally when I'm getting on it pretty good. I need to get out and finish mine, it runs good cold, and fine hot, but I have a problem spot around 130-165 degrees which is in my pilot quantity tuning.
 

oldred95

New member
Mar 17, 2013
10
1
3
The problem seems to be resolved. The LLY pilot quantity table starts shutting the pilot injection off about 200-300 rpm sooner than the LB7 table. Corrected that and made a small timing adjustment and it sounded much much happier.

Has anyone tried the 600 rpm idle with SAC nozzles? I'm curious to see just how quiet the old LB7 can be.
 

oldred95

New member
Mar 17, 2013
10
1
3
Time for the 500 mile review. First of all some balance rates:

Cylinder 1: -1.3
Cylinder 2: -0.4
Cylinder 3: 0.3
Cylinder 4: -1.5
Cylinder 5: 0.2
Cylinder 6: 1.4
Cylinder 7: 0.3
Cylinder 8: 0.7

As I recall with the worn VCO nozzles cylinders 2 and 7 were both in the 7s at operating temp idling in park/neutral. The current balance rates were taken idling at 600 rpm, fuel rate of 8 mm3, 180 ECT, -2 degrees injection timing and 4.5 degrees of pilot timing. The idle is very stable and smooth and this is the first time my truck has ever idled at 600 and liked it. With the VCO's I always had a surge at idle or a surge on the transition from moving to stopped at idle despite adjusting B0756.

After playing around with the timing I've found that my truck likes the LLY B0929 pilot timing table with a somewhat conservative B0910 main injection timing table. The first tank of fuel with mostly highway and some short trip around town and idle time averaged 19.5 mpg. I had to try extremely hard to ever see 19 purely highway with the VCO nozzles. The power is very impressive and I love how the turbo spools effortlessly almost as if it were a VVT turbo. The engine remains almost silent throughout the rev range. Idling at 600 one could easily pull into a drive through and not have to kill the engine to order and the exhaust odor is so clean I doubt anyone would even notice it.