Considering DD'ing 350k mile LB7?

[fl0w3n]

Saw the 04 LB7 I mentioned, the thing is super dang clean. Almost immaculate paint. Interior is super clean, except tear on driver seat. Bone stock except a stereo. Not even an exhaust.

Runs and idles super smooth, pulls good. But Tech 2 tells a different story, looks like injectors are on their way out.

Other than injectors, it needs tcase rebuilt, abs computer seems dead, idler/pitman & leaky gear box, windshield and fuel sending unit.

Fuel rate was bouncing between 5-6mm3

 

[fl0w3n]

Oh, and desired vs actual was fine in park. Putting it in drive/foot on brake and revving it up, they stayed the same within a couple digits.



At 145k, if I do wind up getting it and putting some SAC00's in, would it be dumb not to do a new CP3 at the same time?

 

[DAVe3283]

Depends on how much power you're trying to wring out of it. I've pulled 450+ HP out of 200k+ mile CP3s. I'd personally run it until it gets too weak for your power goals, but replacing it is justifiable if you want to save labor while you're in there.

 

[slowlml]

Personally id wait. I rather save the money and put it towards something else until it becomes a weak link. My labor costs for myself are cheap

 

[fl0w3n]

I’d probably keep it then.

Power goals for this truck are probably stock for a couple years. I don’t want to get into the trans. If there’s truly a trans safe tow tune then maybe something like that at most. I need one of my vehicles to be the solid reliable one that I don’t have to worry about haha. Once I eventually fill that slot with something else than I’d probably build this thing up... but that’s probably after another 100k miles lol

 

[fl0w3n]

Wow I just finally got the 02 back with the rebuilt trans and the repaired ECM from SoCal with @DAVe3283 tune

it kicked a belt for the trans shop, the tensioner looked like it had a little slop so I swapped it for a new Gates tensioner but reused the metal idler from the GM one. I think I had the wrong size belt on though. I put an 118.75” belt on this time and it looks okay.
I’m also not sure my charging system is working. It wasn’t a month ago and I replaced the alternator but the battery light came back on after driving around for a bit.

with all that being said, this thing surprised me with the power. The tune that Dave set me up with combined with a manual trans is pretty gnarly. It just breaks the tires loose through 4th gear once the turbo lights.

my new 04 picking up the 02

 

[fl0w3n]

Just for fun I checked the balance rates and was kind of surprised.
Do these look right for brand new @Brent@LDS SAC45s??

it’s pulling 2mm3 out of the main rate already and a couple of those cyl don’t look great??

 

[DAVe3283]

The main thing you should be looking for is change over time. IIRC you also have an early version of the SAC45 tune I wrote for my brother, so that might be why your main rate is a bit low. I'll try and find time to see if the tune I sent you is up to date or not.

If I recall the tuning process I was more concerned with smooth and predictable operation than exactly matching factory fuel rates. But I do remember making a lot of changes in the low power operation sections, so if you have an older version, that could make things look a bit off.

Sent from my ONEPLUS A6013 using Tapatalk

 

[fl0w3n]

Oh it’s smooth alright, as smooth as it can be with a grabby dual disk clutch.

That makes sense for the main rate. But why would the balance be so different between injectors still?

I also have a CEL for TCM not found lol. I wonder if I can just turn off the indicator for it with my tech 2?

 

[DAVe3283]

Oh oops LOL
Email me the list of codes and I'll sort it out. Never messed with a manual before, just threw that together based off what I was doing for my brother's truck

The balance rate can just be a legit difference between injectors. IIRC the ones in my truck look similar. You just want to keep track of that as a baseline for balance rate, and see if any start moving dramatically from there.

It makes me wonder why I didn't base your tune off a manual file to begin with?? Maybe I couldn't find one? Send me the OS number with the codes too, if you would. The Tech2 will pull that just fine. I don't think you can disable the CEL with it (besides temporarily as a diagnostic).

Sent from my ONEPLUS A6013 using Tapatalk

 

[fl0w3n]

Oh oops LOL
Email me the list of codes and I'll sort it out. Never messed with a manual before, just threw that together based off what I was doing for my brother's truck

The balance rate can just be a legit difference between injectors. IIRC the ones in my truck look similar. You just want to keep track of that as a baseline for balance rate, and see if any start moving dramatically from there.

It makes me wonder why I didn't base your tune off a manual file to begin with?? Maybe I couldn't find one? Send me the OS number with the codes too, if you would. The Tech2 will pull that just fine. I don't think you can disable the CEL with it (besides temporarily as a diagnostic).

Sent from my ONEPLUS A6013 using Tapatalk

No worries, just a funny one to see

I figured it was a legit difference difference between injectors, but like I said I was a little surprised because I guess I was expecting them to be closer. When I ordered from Lincoln I was swayed towards the SAC45's and not the SAC00's because they said they bench tested them and paired together sets that were as close as they could. I guess I didn't ask exactly what the range was per injector, but I just assumed less than a 5.5mm3 swing

I'll see if I can pull it later today.

I need to figure out what's up with the charging system. Replaced the alternator already but the battery light came on after a couple laps around the block and a hard pull and dash voltage says somewhere around 12v. The cable from the alternator to the red junction block is new. I think I need to check grounds

 

[DAVe3283]

I figured it was a legit difference difference between injectors, but like I said I was a little surprised because I guess I was expecting them to be closer. When I ordered from Lincoln I was swayed towards the SAC45's and not the SAC00's because they said they bench tested them and paired together sets that were as close as they could. I guess I didn't ask exactly what the range was per injector, but I just assumed less than a 5.5mm3 swing

Looking back at my SAC75 balance rate thread and my brother's SAC45 balance rates (screenshot below), you are right, yours seem way out.

This screenshot is from midway through the tuning process, we haven't checked them since. I'll try to get a snapshot next time he brings the truck out this way. Though his main rate in neutral with the A/C off is only 6.8mm³, not too far from yours.

But don't jump the gun, let's see if you are running an early version of the tune or not. If it is an early version of the tune, I wouldn't put too much stock in what it says.

And really, I still say the important thing is if the balance rates are changing over time. A cylinder needing more or less fuel than the average could be from other factors (compression, ring condition, valve lash being way out, etc.). In any case, you just want to make sure things are staying somewhat constant.

I need to figure out what's up with the charging system. Replaced the alternator already but the battery light came on after a couple laps around the block and a hard pull and dash voltage says somewhere around 12v. The cable from the alternator to the red junction block is new. I think I need to check grounds

For sure check the grounds, and make sure the connector on the alternator is making good contact / clean. It is also possible you got a bad replacement alternator, though the issue existing before replacing the alternator makes me suspicious of that. I just mention it because I put a high-amp alternator on my car, and a few months later the alternator shorted out, melted its windings, and exploded part of the rectifier bridge on the back. So new doesn't always mean good...

 

[fl0w3n]

Looking back at my SAC75 balance rate thread and my brother's SAC45 balance rates (screenshot below), you are right, yours seem way out.
View attachment 104100
This screenshot is from midway through the tuning process, we haven't checked them since. I'll try to get a snapshot next time he brings the truck out this way. Though his main rate in neutral with the A/C off is only 6.8mm³, not too far from yours.

But don't jump the gun, let's see if you are running an early version of the tune or not. If it is an early version of the tune, I wouldn't put too much stock in what it says.

And really, I still say the important thing is if the balance rates are changing over time. A cylinder needing more or less fuel than the average could be from other factors (compression, ring condition, valve lash being way out, etc.). In any case, you just want to make sure things are staying somewhat constant.


For sure check the grounds, and make sure the connector on the alternator is making good contact / clean. It is also possible you got a bad replacement alternator, though the issue existing before replacing the alternator makes me suspicious of that. I just mention it because I put a high-amp alternator on my car, and a few months later the alternator shorted out, melted its windings, and exploded part of the rectifier bridge on the back. So new doesn't always mean good...

Just trying to learn here, not really sweating it. As long as there isn't chance that I somehow botched the install, but I don't see how anything I could have done (short of dropping the injectors in some rust) would be impacting it.

Good point on other factors. I haven't done a compression check on this motor yet, but at 350k hard miles and judging how bad the prior injectors were knocking, I may have a bad ring or something. I reset lash when I was in there.