My Build Has Started!

[LBZ]

Pull an oil sample. It will tell you whats going on. Have you done a mechanical oil pressure test yet? Your truck sat for a long time, sensors dont like that.

Oil sample will come back bad because of residual zinc additive and break in wear from the last oil that was in it so no point.
Oil pressure never changed since the swap to synthetic and it's above min at idle and just a couple pounds below at 1800 so I'm not terribly worried. If it drops about 5 lbs or so in the next little while then I will be concerned. I have no tools, place, or time to do a mechanical gauge install right now though.

I believe I got H bearings installed not HX so the clearance should be close to stock.

I wish the builder had been a little more diligent in keeping the measurements.....

 

[DAVe3283]

No rattle. The usual smoke and a little lope due to no intake heater and bigger nozzles with an untouched pw table. Around 10C in the morning. I'll let you figure out what that is in F America!

Am I the only American who does all my tuning in metric? It just makes so much more sense, IMO. The ECU does all its math internally in metric, working with kPa of MAP instead of PSI is really simple to ballpark (100 kPa = sea level, 200 kPa = 2 atmospheres, etc). The only part that would be "nice" to work with in °F is intake air temp, but the rest of the pressures and values encountered inside the Duramax don't really relate to what I encounter in daily life, so seeing 140 MPa or 20,300 PSI are both equally unrelatable. Might as well work in the same units as the ECU.

I've never done much with VGTs, but I am a stickler for cold & high altitude drivability on my truck, and I have some similar parts. If you get stumped with the compensation tables, post up any questions and I'll share what has worked on my LB7. Might help your LBZ too. And maybe even keep you from pulling my stunt of getting up at 6 AM and flying out of my driveway to ensure I can drive it above 2000 RPM when the coolant is -10°C (+14°F). Because... what if I need to do that one day? :angel:

Congrats on getting it running. My motor build took 3 years, so I know what it is like to get it going after so long. Once you really dial the tuning, you'll be glad you built it every time you turn the key :thumb:

 

[DAVe3283]

Oil sample will come back bad because of residual zinc additive and break in wear from the last oil that was in it so no point.
Oil pressure never changed since the swap to synthetic and it's above min at idle and just a couple pounds below at 1800 so I'm not terribly worried. If it drops about 5 lbs or so in the next little while then I will be concerned. I have no tools, place, or time to do a mechanical gauge install right now though.

Now, you might want to take my advice with a grain of salt (if my previous post doesn't do that, lol), since I beat the crap out of my stuff. But, here goes:

Don't worry too much about your oil pressure. I broke my motor in by towing up and down the steepest local grade (6%) with a tractor on a trailer behind me. Oil pressure was 50 PSI (350 kPa) at 1600 RPM level ground low heat, but when I would dump the fuel in up the hills, it would sneak down to the low 40 PSI range (~300 kPa). Not much off from yours. This was in cool outdoor temps (~20C / ~70F), so if it is hot where you are towing, I wouldn't be concerned. As long as the piston squirters are opening, you should be good to go.

This was all just standard Delo 400LE 15W40, no break in additives that I recall.

 

[LBZ]

My temps are similar to yours right now. 7-25C.
Worst case I will pull the oil pump and put in a high flow one. At this point, I'm more worried about tuning. I've put everything back to stock as unloaded I was getting a bad timing rattle. Starting over.

 

[LBZ]

Logged my rail this morning. Commanded FPR Current was at 16.3A!!! Does that sound right? Desired rail was at 0, actual was 53mpa.
Something fishy here? Its a modded Danville pump whatever that means.

Posted the log and tune. Went back to a mostly stock tune.

 

[Chevy1925]

Logged my rail this morning. Commanded FPR Current was at 16.3A!!! Does that sound right? Desired rail was at 0, actual was 53mpa.
Something fishy here? Its a modded Danville pump whatever that means.

Posted the log and tune. Went back to a mostly stock tune.

yeah its trying to shut the FPR off and cant. i think you have a sticky FPR when its cold out.

 

[LBZ]

Kinda what I was thinking. And expecting considering how long it sat.

 

[NC-smokinlmm]

Oil sample will come back bad because of residual zinc additive and break in wear from the last oil that was in it so no point.
Oil pressure never changed since the swap to synthetic and it's above min at idle and just a couple pounds below at 1800 so I'm not terribly worried. If it drops about 5 lbs or so in the next little while then I will be concerned. I have no tools, place, or time to do a mechanical gauge install right now though.

I believe I got H bearings installed not HX so the clearance should be close to stock.

I wish the builder had been a little more diligent in keeping the measurements.....

We do it regularly after rebuilds, just tell the testing facility whats going on and I'm sure they could help out if you become worried about it.

 

[LBZ]

A couple logs and my latest tune.

Such as it is......

 

[DAVe3283]

I poked at your latest tune to see if anything jumped out at me.

I know LLY and newer injectors like more timing than the LB7, but your timing seems a bit aggressive at mid-throttle. You could probably stand a bit more timing at high throttle, though.

Out of curiosity, where did you get your fuel pressure table (or what are you trying to do with it if you wrote it)? I am not getting why so much fuel pressure was pulled out in the 2000-2800 RPM range at mid to full throttle.

The rest of the tune seems fairly standard.

If it were me (and my minimal LBZ knowledge), I would put the fuel pressure table back to stock (maybe bump idle to 35 or 40 MPa if you get haze with the big sticks), pull a few degrees timing at cruise and mid-throttle, and blend it in to a bit more timing at full throttle, and see how that runs / what mileage it gets.

 

[LBZ]

I pulled fuel pressure to see if it was the source of my rattle. I was going to add a bit more in. I don't have any problem with rail or smoke so wasn't worried about it much. At least until I start getting a bit more aggressive on the skinny pedal - still breaking it in and a little paranoid yet I guess.

 

[DAVe3283]

I pulled fuel pressure to see if it was the source of my rattle. I was going to add a bit more in. I don't have any problem with rail or smoke so wasn't worried about it much. At least until I start getting a bit more aggressive on the skinny pedal - still breaking it in and a little paranoid yet I guess.

Aah, I follow your thought process. I personally think it is timing, though. 12 degrees with less than 1000 us pulse is a bit much, IMO. But the proof is in the pudding: did the reduced rail fix the rattle?

 

[LBZ]

No it did not. I got a guy on it helping though!
I agree though It's likely timing.

 

[WVRigrat05]

When I had too much timing on my LLY it sounded like a bag of marbles, it sounded bad.

 

[Dozerboy]

The timing in differant on LBZs. I run 11* @ 400-500us cruising. It makes it noisier but I would call it a rattle. Now before I adjusted the coolant mutiplier it rattled before it warmed up. I have just bumped the timing up some and am getting a little rattle not if it's the timing or not though yet.

Sent from my SAMSUNG-SM-G900A using Tapatalk

 

[LBZ]

Well I've got about 5000 miles on the build and mileage still really sucks. Doing the same drive as the first time. Same conditions but cooler this time pulling a pick-up on a car hauler and total weight of that is 6700 lbs at 70mph.

I'd be happy with 12 mpg pulling this load at 70mph. Would have got 15 before the build which bugs me. Getting 9 now.

Not sure what else to try. James helped me get it running a lot better and I've pulled boost in my cruise areas until egts started coming up but it didn't help much.

 

[LBZ]

Changed tunes to an old winter tow tune of the neens that I modified a bit. Mileage improved a bit but of course I'm fighting a 33mph headwind today.

 

[LBZ]

Wish I could figure out how to get rid of this compressor surge though. It's driving me nuts and Danville has been less than forthcoming about where to go to start fixing the issue.

 

[LBZ]

Injectors are done I think. Bad blue haze at idle. Idles a little rough. Balance rates don't look good.

 

[LBZ]

Idle park

Idle drive

I haven't done injector flow back tests but #3 has been leaking like a sieve out of the return hoses and it is always around 4. The others move around a bit. I've never liked the numbers from day one but at that time I chalked it up to rings not being seated but they gotta be by now.