LBZ: Please look and comment on this tune

[mpeters0991]

I made this tune for a lbz. First lbz tune I've made, and I'm having a hard time wrapping my head around all the extra stuff (I had a lb7 before and just before I sold it I was starting to understand it), especially with how the boost tables work with the vane tables, for whatever reason it confuses the shit out of me lol.

What I was going for here was about a 50hp mileage tune with low boost and higher timing around cruising speeds. I haven't gotten gauges on my truck yet so I was wanting you guys to take a look at the tune and tell me what you think. I'm planning on getting gauges here in a month or two, so dont raz me to bad about that lol.


Any criticism you guys have I really appreciate it as long as its constructive. I'm just trying to learn.

Thanks
Michael

 

[slipclutchms]

One the vane position table what was your thought process? The fist thing I notice is that huge "dead spot" you created. I am thinking you were trying to build an LB7 idle tune.....To do that, log your truck and watch the tune tool to see what cells are being referenced to idle...(hint, looks like the 600 to 800 rpm region with the 25% position would be fine)...Work on your timing tables, use the calculator. There is a region of rather high timing mid throttle but then it drops into a hole. Think about where you are in the tune as your coming on throttle. RPMS are increasing as well as commanded fuel. How would the truck run using this table? 7 degrees, 10 degrees, -0.4 degrees, 10 degrees, 24 degrees. Need to smooth these transitions. Pulse table looks good.....

 

[slipclutchms]

See attached screen shot

 

[mpeters0991]

Yeah I did the lb7 idle but then I think the spot you referring to was where I lowered vane position thinking that was right about the cruising range (I work for the railroad and was out of town sitting in the hotel board when I made this, which is the reason I haven't logged anything before I did this) and that would lower the boost which would yield better mileage.
I can say pretty much the same for the timing table to I guess. I raised the timing right about where I figured the cruising range would be.
I suppose the way I went about making these changes were just to drastic correct?


I was really wanting to make a tune that would yield good mileage within cruising range but then outside of that it would come more alive. That was the goal anyhow.

 

[mpeters0991]

Does that explain my reasoning for the way I did it? Am I wrong for thinking that way?

 

[mpeters0991]

bump..... can I get any more comments on this? I appreciate all the help

 

[Harbin_22]

In my experience with lower boost tunes, the vane table is not near as important as the commanded boost table is. I'm on my phone so o haven't looked at the tune to see your boost tables, but just an fyi.

 

[paintballrepins]

IIRC, and I'm not a tuner by any means, but I agree with Harbin. The ECM attempts to reach the commanded boost on its own, simply using the vane position table as a reference to get close.

I could be wrong...

 

[mpeters0991]

So I should more or less just leave the vane tables alone and instead lower the desired boost tables in the cruising range i want?

 

[Harbin_22]

So I should more or less just leave the vane tables alone and instead lower the desired boost tables in the cruising range i want?

That would be my suggestion.

 

[mpeters0991]

Alright thanks man. I'll mess with that a little. Hopefully I'll get my gauges here soon and I'll take her out and give her a shot.

Now what is your opinion on my timing table (when you get chance to look at it) after I explained my reasoning for why I did it the way I did?

 

[christopherglenn]

Here are my current LBZ tunes (ecm and tcm). I am running them on my truck, and they seem to be ok.

~25% increase in power over stock, shifts at 3600-3700 (wot), grade braking over 2k, tow/haul stays above 2400rpm, until ~50mph (California towing speedlimit is 55). I tow my 18k TH with this tune.

I have a stock tranny, so it defuels (to stock) before shifting into 5th. If you are only going to try the ecm tune and have a stock tranny, put it in 4th, or the 4-5 shift could be exciting.
I have a cheetah 64, but the top boost *should* be at the max of the stocker. Some input would be nice, as I am making things up as I go along.

 

[mpeters0991]

Alright here's a little different tune. I kind of left changed the boost tables a little and used the stock vane position tune

 

[mpeters0991]

So I went and test drove that tune and it did something I thought was very weird and I'm not sure what I did to cause it. I would speed up and and when I'd let off the gas it would try and keep giving it self more fuel/power what ever you want to call it to keep going and it would do that through the gears until I came to a stop. Then when I stopped I revved it to like 2500 rpms and it acted like it wanted to keep going up in rpms so I shut it off and loaded the old tune back on and it worked fine. Any ideas what I did wrong?
Also when it would rev its self it sound a lot like your traditional diesel.

 

[slipclutchms]

Did you mess with pilot or post injection? Timing pulse or fuel command? I haven't looked thru the tune yet.... I will tomorrow

 

[christopherglenn]

b1102
0 means 0, you are injecting fuel at 0 foot pounds of desired torque.
b0720
0.1 mm3 line should show the time needed to open and close the injector, not actually inject a measureable amount of fuel. Copy and paste the 0.1 - 5 mm3 from the stock table into your tune. The extra low tables will help with the idle.
Be careful with the timing, you didn't correct the "main injection correction" section when you advanced the timing, when cold you are running ~16 degrees of timing in places.

 

[mpeters0991]

Alright thanks man. I'm not sure how I didn't notice the screw up in the torque tables.

And thanks for the advice on the timing deal. What table number is it your referring to?

 

[christopherglenn]

from b0952 to b0957.

I would zero out from b0952 to b0989, and put things back one at a time. (they are all temp related, so you are pretty much stuck to one per day). There are coolant temp @ altitude (times 3), IAT (Intake are temp), AAT (ambient air temp).
If you set b1021 to 2, you will get the main injection, and preinjection 1 only. then you can ignore everything related to pre2 and pre3. I have NEVER logged pre2 doing anything, I have never heard of pre3 doing anything.