Advanced Engineering Tech - Tuning Docs, VE/MAF, SES Lights, FAQS + more!

-This Sticky is a consolidation of useful discussions and Tuning docs that have been brought up over the years. As new information is added I will update the Date in the thread title.

-If there are any topics you wish to discuss or think should be added to this post feel free to post up This sticky should be here to serve the tuning community, so should contain what YOU want to see/discuss

FAQ
If I reset my PCM/Disconnect my Battery/Battery goes dead will I lose my tune?
---Nope... your tune is stored in flash memory... only way to lose it is if you reflash your PCM. It may idle poorly at first while the car is "relearning" how to idle however. This should only last a few minutes.

I have an SES light. Can I disconnect my battery/pull the PCM fuses to reset it, and then pass OBDII Emissions?
---Usually no... once you reset the PCM (wether by removing power or clearning w/a scanner) the PCM sets the readiness codes to "not complete" for the various emissions tests. You need several driving cycles usually (hot and cold starts) before the readiness tests will complete.

What's the best Tuning software for me?
---The best is a personal decision. Here is some info that will help you decide. (http://www.ls1tech.com/forums/showthread.php?t=368718)

Detailed Descriptions located at:
http://www.ls1tech.com/forums/showpost.php?p=2863388&postcount=20


Quick Links:
Learning to Tune:
--Tuner Software-Tuning 101 (http://www.ls1tech.com/forums/showthread.php?t=284479)
--HP Tuners .bin Repository (http://www.ls1tech.com/forums/showthread.php?t=190486)
--Predator Tuning 101 (http://www.ls1tech.com/forums/showpost.php?p=2652650&postcount=10)
Fuel Trim Cells:
--Fuel Trim Cell Discussion (http://www.ls1tech.com/forums/showthread.php?t=125583)
Injector Tuning:
--Tuning SVO Injectors (http://www.ls1tech.com/forums/showthread.php?t=326601)
--Injector Scaling Calculations (http://www.transamws6.net/HPTuners/injectors.xls)
--Injector Duty Cycle Calculations (http://www.ls1tech.com/forums/showthread.php?t=306296)
MAF and VE Tuning:
--How the MAF Works (http://www.ls1tech.com/forums/showthread.php?t=363392)
--MAF Table Tuning (Dialing in the MAF Table) (http://www.ls1tech.com/forums/showthread.php?t=256989)
--VE Table Cracked! (http://www.ls1tech.com/forums/showthread.php?t=149741)
--VE Table Tuning -- Now Hesitation when driving (http://www.ls1tech.com/forums/showthread.php?t=84933)
--Tuning VE via fuel trims (http://www.ls1tech.com/forums/showthread.php?t=304025)
Torque Converter/Shifting Tuning
--Torque Converter locks/unlocks after larger converter install -- FIX (http://www.ls1tech.com/forums/showthread.php?t=162767)
Idle Tuning
--Stop drilling those Throttle Bodies! (http://www.ls1tech.com/forums/showthread.php?t=177230)
--Idle Operation Part 1 (http://www.ls1tech.com/forums/showthread.php?t=193103)
--MAF and Running Airflow Tables (http://www.ls1tech.com/forums/showthread.php?t=290064)
Diagnostics/Troubleshooting/Other
--Service Engine Soon (SES) Lookup and Diagnostics (http://www.ls1tech.com/forums/showthread.php?t=209783)
--Detailed Diagnostic Information (http://www.ls1tech.com/forums/showthread.php?t=103710)
--GM Driving Cycle (Completing OBDII tests) (http://www.transamws6.net/HPTuners/gm_driving_cycle.txt)
--*NEW*IAT vs Resistor vs Reported Temperature (http://www.transamws6.net/HPTuners/Temp_vs_Ohms.jpg) *NEW*

this is an awesome collection of information. definitely sticky worthy!!

Horist you're my hero. <3

Finally! Very nice. Thank you.

Thank you for your efforts! :)

-franklin

Thanks horist!
This was one of the most exciting threads I'd ever read ->VE Table Tuning -- Now Hesitation when driving.

NoGo and ChrisB - nuff said. :D

Looks Awesome! Thanks!

Nice. The forum looks much better all cleaned up!

horist - can you include gameover's "Idle Operation Part 1" thread? It includes Part 2, also. Thanks. :cheers:

-> http://www.ls1tech.com/forums/showthread.php?t=193103&page=1&pp=20

This might help as well. It takes the thread above me and puts it into a spreadsheet format. Determines the Running Airflow Tables

MAF and Running Airflow Tables (http://home.insightbb.com/~black02ss/Calibration.xls)

Included now in the help file Bill. :)

This might help as well. It takes the thread above me and puts it into a spreadsheet format. Determines the Running Airflow Tables

http://home.insightbb.com/~black02ss/RAFTABLE1.0.zip

What PID's do you need to log for your spreadsheet?

Bill
:engarde:

Edited my above post to include a updated sheet with a help file.

hey, could you link to http://www.allmod.net/hpt/ officially? that's where my MAF calibration stuff is, which i know is linked in txhorns' thread, but it's kinda buried.
thanks

Awesome info.... Thanks for getting this info together.

added Silverhawk_02TA's VE tuning page... thanks

Thanks Silverhawk_02TA. It looks good. I am going to be giving it a try this weekend.

Bill
:drive: :chug: :judge:

Added
http://www.ls1tech.com/forums/showthread.php?t=306296

for Injector duty cycle calcs

The link for "Idle Operation Part 1" in the lower section (not the top one) is broken. :judge: Top link works fine.

Thanks so much for putting this together, it's been really helpful.

Bad30th

thanks, fixed the link

Title: Tuning 101
Description:Tuning Documentation for Newbs. Contributed by james99ws6 and contains information from many enthusiasts
Purpose:Newb tuning assistance
Location: http://www.ls1tech.com/forums/showthread.php?t=284479
Quick Jump: http://www.transamws6.net/HPTuners/ls1tuninginfo.doc
----------------------------------------------------------------

Title: HP Tuners .bin file Repository -- Search for bins , upload your own bins!
Description: Provides access to hundreds (175 at last count) of .bin files for your viewing pleasure.
Purpose:Tuning aid, view what others have changed and learn from them
Location:
http://www.ls1tech.com/forums/showthread.php?t=190486
Quick Jump: http://www.horist.com/hptuner/
----------------------------------------------------------------

Title: MAF Table Tuning (Dialing in the MAF Table)
Description:Useful information on dialing in your MAF tables.
Purpose:Tuning your MAF readings to match actual air entering the engine
Location: http://www.ls1tech.com/forums/showthread.php?t=256989
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Title: VE Table Cracked!
Description:Contains many valuable mathmatical and theoretical formulas, discussion, and documents about the Volumetric Efficiency Table
Purpose:Volumetric Efficiency Discussion
Location: http://www.ls1tech.com/forums/showthread.php?t=149741
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Title: VE Table Tuning -- Now Hesitation when driving
Description:Further Discussion on VE tuning and how to fix hesitation issues via tuning
Purpose:VE Tuning and hesitation fix
Location: http://www.ls1tech.com/forums/showthread.php?t=84933
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Title: Torque Converter locks/unlocks after larger converter install -- FIX
Description:How to fix when an aftermarket Torque Converter will not stay locked
Purpose:Torque Converter Lockup Fix
Location: http://www.ls1tech.com/forums/showthread.php?t=162767
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Title: Stop drilling those Throttle Bodies!
Description:Discussion on achieving quality Idle w/out drilling your Throttle Body and without Computer Tuning
Purpose:Idle Characteristics
Location: http://www.ls1tech.com/forums/showthread.php?t=177230
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Title: SES Code Lookup
Description: Several sites for looking up Service Engine Soon lights
Purpose: Code lookup and diagnostics
Location: http://www.ls1tech.com/forums/showthread.php?t=209783
Quick Jump: http://www.obdii.com/codes.asp
Quick Jump: http://gearchatter.com/
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Title: Detailed Diagnostic Information
Description: GM LS1 Information PDF file
Purpose: Interesting read describing the various sensors and how they work...
Location: http://www.ls1tech.com/forums/showthread.php?t=103710
Quick Jump: http://www.hsvdriversclub.co.uk/ls1.pdf
Quick Jump: http://www.transamws6.net/HPTuners/holden_ls1.pdf
----------------------------------------------------------------

Title: Fuel Trim Cell Discussion
Description: Discussion of conditions required to enter certain fuel trim cells (FTCs)
Purpose: Discuss and explain Fuel Trim Cell mappings
Location: http://www.ls1tech.com/forums/showthread.php?t=125583

----------------------------------------------------------------

Title:Idle Operation Part 1
Description:Discussion of Idle operation and Idle tuning. Special thanks to Gameover of HP Tuners for sharing this very useful information.
Purpose:Idle tuning
Location: http://www.ls1tech.com/forums/showthread.php?t=193103
----------------------------------------------------------------

Title: MAF and Running Airflow Tables
Description:Excel spreadhseet for calculating MAF and Running Airflow Tables. Special thanks to Black02SS for this contribution.
Purpose:Compliments the Idle Operation Threads
Location: http://www.ls1tech.com/forums/showthread.php?t=290064
----------------------------------------------------------------

Title: Predator Tuning 101
Description: Learning to tune with a Predator Handheld programmer
Purpose: Writeup on tuning with a diablo sports Predator
Location: http://www.ls1tech.com/forums/showthread.php?t=294713
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Title: Guide to tuning VE via fuel trims.
Description: Writeup on VE tuning via the fuel trim tables. Special thanks to Silverhawk_02TA for taking the time to do this writeup.
Purpose: Dialing in the volumetric efficiencty table
Location: http://www.ls1tech.com/forums/showthread.php?t=304025
----------------------------------------------------------------

Title: Injector Duty Cycle Calculations
Description: Writeup showing how to calculate Injector Duty Cycle.
Purpose: To determine how close you are to maxing your injectors. Rule of thumb is you don't want to be higher than 80%
Location: http://www.ls1tech.com/forums/showthread.php?t=306296
----------------------------------------------------------------

Title: Injector Size Calculations
Description: Excel spreadsheet for calculating Injector Sizes
Purpose: To properly calculate Injector Sizes. Thanks to RedHardSupra for this file!
Location: http://www.transamws6.net/HPTuners/injectors.xls
----------------------------------------------------------------

Title: Tuning SVO Injectors
Description: SVO Injectors are rated at 40psi , not 3 bar. useful info on tuning these injectors
Purpose: Assist with properly dialing in IFR tables w/cars running Ford Motorsports SVO Injectors
Location: http://www.ls1tech.com/forums/showthread.php?t=326601
----------------------------------------------------------------

Title: GM Driving Cycle
Description: GM OBDII Driving Cycle.
Purpose: Following these instructions should cause all OBDII readiness Tests to complete.
Location: http://www.transamws6.net/HPTuners/gm_driving_cycle.txt
----------------------------------------------------------------

This link is no longer any good....I would love to read the information.

Would someone send me the file?

W


Title: Detailed Diagnostic Information
Description: GM LS1 Information PDF file
Purpose: Interesting read describing the various sensors and how they work...
Location: http://www.ls1tech.com/forums/showthread.php?t=103710
Quick Jump: http://carprogrammer.com/Z28/PCM/LS1/Holden_LS1.pdf
----------------------------------------------------------------

This link is no longer any good....I would love to read the information.

Would someone send me the file?

W


Title: Detailed Diagnostic Information
Description: GM LS1 Information PDF file
Purpose: Interesting read describing the various sensors and how they work...
Location: http://www.ls1tech.com/forums/showthread.php?t=103710
Quick Jump: http://carprogrammer.com/Z28/PCM/LS1/Holden_LS1.pdf
----------------------------------------------------------------

its still here :) http://www.hsvdriversclub.co.uk/ls1.pdf

also added this (^^^)PDF to my personal server... so long as I don't run too close to using up my bandwidth, I'll let it stay

Added SVO Injector tuning post

i dont know if there is any full write up i have done or someone else has thats out there but the IAC count and effective area table seems to be comming up a lot maybe we can add this. i think i wrote it all up in here somewhere...

please do, make a nice preset .cfg for it too, i have few big cam cars with funky idles coming up soon.

ok if i get a chance when i get home ill type it in here and ive got to get my computer online to load up the config, if not ill post up the stuff i logged and someone can make the config.

search and search man, most of the stuff still applies, just might be different tables

Added an FAQ section. If anyone has any ideas for simple 1 line questions and answers (well maybe more than 1) that are asked commonly (started because I noticed 2 threads today asking if their tune will be lost due to resetting the PCM) let me know...

Just send me or post up here something like:
Q: What type of FAQ should I make?
A: Whatever kind you want

Added IAT vs Temp vs Resistance chart.

I've read all the FAQs and stickies. Maybe it's the way the info is organized and presented but I don't feel comfortable beginning my foray into changing the program yet.
My mind works best when I get comfortable with each step in the title of this post in order.
Theory
As far as theory is concerned the goal is to get the optimal combustable mixture and ignite it at the optimal time. The old gas plus air plus spark equation.
a) Gas is the amount of fuel supplied by the injectors. This is further broken down into the size of the pipe (injectors) and the length of time they are pumping.
b) Air is the molecules of oxygen present in the combustion chamber.
c) Spark is when the spark plug fires during the combustion stroke.
__________________

AFR is the ultimate indicator of how well the process is going so the first step would be to log wideband O2 sensor data and see where in the operating range of the engine the process is amiss.

Quote from gameover:
PCM first works out airflow, then fuel.
It calculates it has X grams of air in the cylinder (MAF/VE table), it knows it has a target AFR of Y, therefore it needs to inject Z grams of fuel. Z = X / Y
Once it has worked out it needs Z grams of fuel, it then looks to the IFR table to work out how long to pulse the injector for to get Z grams of fuel.

Speed Density
Air density is calculated from the IAT (intake air temp sensor) and the MAP (Manifold Absolute Pressure). ie Higher IAT = less dense air, Higher MAP = more dense air. Combined with information from the CKP(crankshaft position sensor) the PCM detrmines the required injector pulse.

Mass Air Flow
Under normal conditions the MAF (Mass airflow sensor) works in conjuction with the speed density system to calculate the required injector pulse. If the MAF malfuctions then the speed density system is used exclusively. The ECT (engine coolant temperature sensor) and the TP (throttle position sensor) also provide inputs to determine injector pulse width.

Open Loop
This system is used when the O2 sensors have not come to full operation temperature or they have failed. Injector pulse width is detremined by the
the inputs from the CKP, MAF,MAP,IAT,ECT and TP.

Closed Loop
The O2 sensor input is used to modify the injector pulse width signal determined in Open Loop to achieve an approximate 14.7 to 1 AFR (air fuel ratio)

Power enrichment
Fueling changes dictated by the the O2 signals are ignored. AFR is richened based on large TP changes

STFT (short term fuel trim)
Corrections to the AFR based on O2 inputs. These are not stored by the PCM.

LTFT (long term fuel trim)
If the PCM continues to adjust the STFT for an extended time period for a particulat cell in the trim table the PCM will change the value in the LTFT table cell and reset the STFT adjustment to zero. Each cell in the LTFT represent a specific engine operating range. When the engine is operating in that range the PCM looks to the LTFT table and makes the correction to the injector pulse width indicated in that cell. The STFT continues to monitor AFR and further adjusts this Injector pulse width if necessary.
Information in the LTFT table is lost when power to the PCM is lost.


__________________

Programming methodology: There are two schools.
a) Log data on the road or on a dyno and simply bump the numbers up or down on a particular table to get the right AFR and timing. What the numbers actually mean in the tables are irrelevant.
b) Log data on the road or on a dyno and calculate the "correct" values for the cells in various tables.
__________________
Mechanics

What are the sensors that provide the data to the PCM software so...
the software can compare these sensor values to those in various lookup tables and then provide an output signal to:
1) the injectors
2) the coils

So I would like to have an excel table which shows cause and effect listing:
a) sensor
b) what it measures
c) what are it's units of output
d) how to convert this output to meaningful information such as temperature in degrees celsius
e) what PCM lookup tables it values are compared to
f) based on this comparison, what the PCM software outputs to which device, compares to a further PCM lookup table, or modifies a lookup table.

Consensus information I have gathered so far:

1)Timing is primarily adjusted through modification of the High Octane Spark Advance table.

2)Adjusting AFR is a little more complicated and controversial in regards to what table or tables should be adjusted.
-some say to leave the VE (volumetric efficiency) table alone and adjust the MAF (MAF vs Frequency Table).
-others say to adjust everything, PE (power enrichment) , VE and MAF.

3) Everyone does agree that LTFT (long term fuel trims) are a critical indicator of how things are going. Adjusting them exclusively does nothing as they will just go back to where they were as a result of STFT adjustments. You must correct the AFR through adjustment of table values (VE and MAF) and then zero (or as close as possible with a bias toward negative which makes the mixture leaner) the LTFTs.

__________________
Tools

Then we can use the tools, of which there is the most information on, to modify the look up tables in order generate the signals we want, when we want them, to the injectors and coils.

I am happy to accumulate contributions to the building of such a table.

How accurate is the injector scaling? My pcm shows something different for my 42lb SVO injectors. I have HP Tuners and I would like to know what values to change if I switched from 42 to 60lb Seimens. Thanks.

^^^ 42lb brand (what) to 60lb (brand what) ? Vince .... PM me the info and also make a post about it here (PCM section) .. (if both siemens .. i'd think they'd be linear... so the standard formula would work.... but would be best to post up anyways...... at your power level.... it may not be linear)

^^^ 42lb brand (what) to 60lb (brand what) ? Vince .... PM me the info and also make a post about it here (PCM section) .. (if both siemens .. i'd think they'd be linear... so the standard formula would work.... but would be best to post up anyways...... at your power level.... it may not be linear)

I sent you an email with my current settings.