Tuning Question - Tow Tune

Physiksgeek

Member
Jul 31, 2022
37
3
8
Crane Hill, Alabama
Hey....I'm new to the tuning process. I do not do it as a business, for friends, or for money. It is all strictly personal. My free time is dedicated to fishing. So I have spent the last few months when not doing that just trying to learn the lingo, relationships, correlations and most importantly what not to do. So for all that I do not know....I think I have a question.

During my "new guy introduction" DozerBoy said a lot of the info was out there. I see/saw/seen that to be true. Shout out to HondaRider552, DozerBoy, JoshH, Cobra#3747, McRat and I apologize to all the others I cannot remember.

This question involves our good friend HondaRider552 Tow tune for an LBZ. I am in the "risk averse" stage still. Even when that wears off I am still not looking to run Crazy Larry tunes on my daily driver. Anywho.....as I compare this 50HP tow tune to my stock LBZ file table B1020 is scaled different. The question(s) are/is
1, why would this be?
2. What does it "drive"
3. if its "not normal" is it an issue that I should be concerned with (from a "you should never do this because of a runaway diesel killin baby rabbits" standpoint not a "bad part" type standpoint)?
4. If its a non-issue.....any speculation as to what I could/should see as different? Kinda dovetails into question 2.


Essentially my scale in table B1020 runs from 0 - 2.5A where as in the tow tune it runs from 0 -1.02A. Now from what I know about electronics.....though they are both linear I cant just willy nilly change the scale of something for multiple reasons but, the slope of rise and/or fall being the most important.

This is mine -
1661901018466.png

This is from the file -
1661901388757.png




I have other questions I'll start new threads over but right now I appreciate any input on this one. Thanks
 

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
15,271
1,564
113
Mid Michigan
If all your questions pertain to the same tune, please keep them all in one thread.
 

2004LB7

Well-known member
Dec 15, 2010
6,280
1,683
113
Norcal
The only thing I can think of is the tuner must have been trying to fix a problem like if he modded the regulator and it was outputting a different pressure or maybe was using a different regulator. I would change that value back to stock if you plan on using the tune. was there any notes in the comments tab indicating what was done? or perhaps a clue in the history?
 

Physiksgeek

Member
Jul 31, 2022
37
3
8
Crane Hill, Alabama
Thanks-There were no notes. I have not used the tune just been comparing it to my stock tune. When looking at the differences between this was something I noticed. Being it was an “LBZ” tune could not find a reason for the difference.

To your point I did wonder if it was because of a fuel pump maybe? I do not have one. But if other mods to fuel were made like you said it could explain.

Thanks again.
 

Physiksgeek

Member
Jul 31, 2022
37
3
8
Crane Hill, Alabama
No mines an LBZ. It was called an LBZ tow tune (paraphrasing). So my assumption was same same. You could have a point though if it was an lb7 tune that was modified to an lbz tow tune. It may account for the scaling differences.
 

2004LB7

Well-known member
Dec 15, 2010
6,280
1,683
113
Norcal
I'd have to double check but I don't think the LB7 has that table so there wouldn't be any adjustments to make it work on another engine
 
  • Like
Reactions: 08lmm72mm

2004LB7

Well-known member
Dec 15, 2010
6,280
1,683
113
Norcal
What pressure is this table monitoring ? FPR? If it is just run it how you want then log it and see how it acts/drives then adjust from there.
it's not really a monitoring table but a conversion table for the ECM to use to convert the relative voltage to current based on the resistance of the coil in the regulator. a non stock or modified regulator may require some adjustments to get the regulator to behave correctly. not really something that would need adjustment so it's odd that it was changed
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,065
4,736
113
Phoenix Az
Brian did all kinds of weird shit with tuning way back then (hondarider). im 90% sure he had the stock FP sensor in there still so i dont know why he fucked with it. Id set it back to stock and see if you have an issues. wouldnt hurt to compare the fuel pressure tables between your stock and his and see if there is anything weird.

he might have tried to read higher than stock fuel pressure on the stock sensor but i dont think it worked.

either way, its just a sensor scaling table against voltage. usually used when you use a difference sensor that can read higher than stock but still uses the same 5v input.
 

2004LB7

Well-known member
Dec 15, 2010
6,280
1,683
113
Norcal
Brian did all kinds of weird shit with tuning way back then (hondarider). im 90% sure he had the stock FP sensor in there still so i dont know why he fucked with it. Id set it back to stock and see if you have an issues. wouldnt hurt to compare the fuel pressure tables between your stock and his and see if there is anything weird.

he might have tried to read higher than stock fuel pressure on the stock sensor but i dont think it worked.

either way, its just a sensor scaling table against voltage. usually used when you use a difference sensor that can read higher than stock but still uses the same 5v input.
is that table for the pressure sensor? if so your explanation for trying to read higher pressure makes sense. I thought it looked more like something for the regulator but was having a hard time coming up with a reason to alter it
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,065
4,736
113
Phoenix Az
is that table for the pressure sensor? if so your explanation for trying to read higher pressure makes sense. I thought it looked more like something for the regulator but was having a hard time coming up with a reason to alter it
yeah its for the sensor from what ive found on efi live forum and looking in efi live
 

Physiksgeek

Member
Jul 31, 2022
37
3
8
Crane Hill, Alabama
I appreciate all the feedback. Was mostly curious about possible outcomes. In my mind best case scenario was if I left it with the table I had(stock).....since it was over a larger Amp range....the slope would not be the same but maybe it would be more granular or smooth(er). But, that was in my mind so there comes the questions cause the flip side to it....in my mind.....was if it fell off the chart once it hit 1.02....because it is a reference....what would happen then?

I have compared the tables but not with that in mind......that is a good idea. Yer saying if he was trying to exceed the 26,xxx'ish psi it may account for it? I guess he could of also been pullin the fuel out pretty hard help with the turbo brake side of it. I do know he was doing some pretty serious stuff up in the 4000 rpm range.....if I remember correctly he was pullin fuel out though....I'd have to look again but the rpms made me shudder...lol

This is a link to the tune....EagleBay brought it back in the very last post on page 2 if interested.

tune link

Thanks
 

08lmm72mm

Active member
May 13, 2019
528
164
43
Saskatchewan, Canada
I think what he's saying since it's a table for the fuel pressure sensor it might be scaled to work with a higher pressure sensor installed possibly one from PPE. If anything changing it from what it should be stock would cause your truck to maybe read the wrong pressure and cause issues but I'm just speculating
 
  • Like
Reactions: 2004LB7