Learning to tune!

Cnixon160

Active Member
I can throw you a rough base tune together pretty easily, as for the wideband issues pick up one of these units, https://www.twistedbuilds.com/tb-wideband-controller-and-gauge/, I've used several with no issues and they can be left installed indefinitely, you will however need to have the mechanical side of things correct or your tune will be compensating for a physical issue

Edit: forgot to mention that product is designed to completely replace the factory narrow band sensor and will feed the ECU an interpolated signal in it's place
 

Keckster

Well-Known Member
I can throw you a rough base tune together pretty easily, as for the wideband issues pick up one of these units, https://www.twistedbuilds.com/tb-wideband-controller-and-gauge/, I've used several with no issues and they can be left installed indefinitely, you will however need to have the mechanical side of things correct or your tune will be compensating for a physical issue

Edit: forgot to mention that product is designed to completely replace the factory narrow band sensor and will feed the ECU an interpolated signal in it's place
I'm not having any wide band issues anymore. I ended up using the PLX wideband with narrowband simulation. Would it be to much to ask to have a rough tune thrown together with some notes on what you did?
 
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Cnixon160

Active Member
min not having any wife and issues anymore. I ended up using the PLX wideband with narrowband simulation. Would it be to much to ask to have a rough time thrown together with some notes on what you did?
Post up your stock file and a rundown of the mods and I'll make a base file from it with a rundown of what was changed and why, it'll be a day or two as it'll be a purely free-time thing but informative none the less
 

Keckster

Well-Known Member
You sir are a legend! I've attached both the stock file I pulled from the car and the tune I tried to start up with a text document of the changes I made. I also attached the spreadsheet I found with injector tables for the lsj 60lbs Siemens injectors I have. I've read on a few forums from hptuners that it is hard to get the siemens injectors to idle. Strangely, when I forgot to hook up the brake booster and had a big boost leak it would idle rough but with the leak fixed it wont idle at all. My guess is something to do with air . My list of engine mods include:

ZZP Stage 2 SC Cam
-ZZP S2 is 216/218 @ 1mm and 10.78mm/10.69mm lift, 111 LSA
82# valve Springs
Balance Shaft Delete w/ short chain
Siemens 60lbs injectors
4340 Connecting Rods
JE 9.5:1 coated pistons
ATI Oversized Harmonic Damper
2.7 inch SC Pulley

Turns out Excel files are not allowed to be uploaded but here is the link to the lsj tuning resource I've been trying to use where I found it:
 

Attachments

Keckster

Well-Known Member
I’ve finally received my MAF tube and tried starting it up to see if that was the problem but it is still doing the same thing of just one or two fires then dying
 

Keckster

Well-Known Member
Update on the idle issue! Turns out my throttle body or tps was bad... Replaced it and now it can hold idle! Obviously it still needs so work to make it smoother but at least it'll run on its own!
 

Kyle

Active Member
I know I'm late to the party, and it sounds like you have your idle issue solved which is great! That said, I've heard the cobalt injectors have a pretty unique spray angle and most injectors need to be modified to spray at the proper angle (I don't know how that is actually done). Cobalts are known to have idle issues when changing injectors.
 

Keckster

Well-Known Member
I know I'm late to the party, and it sounds like you have your idle issue solved which is great! That said, I've heard the cobalt injectors have a pretty unique spray angle and most injectors need to be modified to spray at the proper angle (I don't know how that is actually done). Cobalts are known to have idle issues when changing injectors.
I ended getting new injectors from Fuel injector connections with a special adapter to change the spray pattern. I also switched from the 60# siemens injectors to 80# bosch injectors which from reviews are much better consistency and quality
 

Kyle

Active Member
I ended getting new injectors from Fuel injector connections with a special adapter to change the spray pattern. I also switched from the 60# siemens injectors to 80# bosch injectors which from reviews are much better consistency and quality
Well keep up the good work! As far as Goblin engine mods go, I'm still totally stock (LSJ) . In the very near future I would like to do some mods like injectors, pulley, valve springs, dual pass and maybe a cam. Being a spectator of the journey a lot of you guys go on while learning to tune and boost your cars even further is really inspiring and keeps a lot of us motivated. So, thank you!
 

Keckster

Well-Known Member
After lots a lots of research, conversation, and experimenting I believe I have gotten the hang of the first step in tuning. I'm gonna try and explain the best I can but feel free to add to the conversation or even correct me if I am wrong.

Tuning Step 1: MAF Calibration
As always the hardest part about learning something new is jumping in head first and learning. I've come across two methods on tuning the MAF and cannot find a great explanation between the two.





-Method 1: EQ Ratio vs. MAF Frequency
This method is the most commonly found when trying to research tuning. With this method you disable most calculations and tables in the computer.​
Step 1: Scanner Setup
We need to setup a graph in VCM scanner to monitor EQ ratio vs the MAF frequency which I believe requires the hpt pro addon to interface with a wideband gauge directly but I could be wrong. You can also run a wideband signal to the AC pressure sensor wire on the ECU to log the AFR voltage in hptuners. This requires some extra math and wiring setup so let me know if you would like a write up on that.​
Lets setup our Math via the Tools>Math Parameters>Maths-User. Choose one of the "User Math #" and setup the window like the photo:​
LSJ AFR error.PNG
*Note: the PID 50120 is shaded red because it is set to a generic sensor that the P12 ECM does not have. If you are tuning using hptpro with a wideband connected you will replace this PID with your WB
Once your custom math parameter is setup you can find your way over to the graphs tab in the scanner. Once there we will right click and go to "Graphs Layout". Once the graphs layout dialogue box opens we will add a graph and fill in the following fields:​
LSJAFRerrorGraph.PNG
*Note: The Values for the MAF Frequency were acquired by copying the axis from the MAF table in VCM editor
Step 2: MAF only setup
In order to calibrate our MAF sensor we need to make sure our car is only controlling fueling via the MAF readings. I have not personally used this method and do not know how the car will initially react untuned running on just the MAF so make sure to use your senses if it seems to be running poorly.​
!!!!!make sure to save an ASFound file so if you need to go back to completely stock you can!!!!!
VCM Editor MAF only setup
I used a lot of the info for setting up for MAF only tuning using the templates provided by @ctuinstra in his great post HP Tuner Templates and [SC TUNE GUIDE #2] HPTuners; Using Templates
Changes marked with a ** will be reverted post tuning. Make sure to take note of the original values
**Disable VE Tables**:
Engine>Airflow>Dynamic>Dynamic Airflow​
High RPM Disable -> 300 rpm​
High RPM Re-enable -> 200 rpm​
Setting these will disable the Volumetric Efficiency tables, By disabling these tables the car will not adjust fueling via calculations using cylinder air mass.
**Force Open Loop**:
Engine>Fuel>Oxygen>ECT vs. Startup ECT​
Set entire table to a coolant temp the car will not reach (I.E. 300 C)​
Engine>Fuel>Oxygen>Delay​
Set Table to a very large number (I.E. 5000)​
Engine>Fuel>Oxygen Sensors>Monitoring> O2 Readiness ECT​
Set entire table to a coolant temp the car will not reach (I.E. 300 C)​
By forcing the car into Open loop it will ignore readings from the oxygen sensors and will run strictly off of the MAF tables to control fueling
**Disable Deceleration Fuel Cutoff(DFCO)**:
Engine>Fuel>Cutoff, DFCO>Deceleration Fuel Cutoff​
Enable ECT -> 490 C​
Disable ECT -> 480 C​
Enable RPM -> 8192 rpm​
Disable RPM -> 8191 rpm​
Engine>Fuel>Cutoff, DFCO>Vehicle Speed​
Enable Speed -> 300​
Disable Speed -> 290​
These settings disable fuel cutting off as you let off the throttle. This can cause burbles and pops while out driving should be ok so long as they don't seem to aggressive.
Now that our vehicle is set to MAF only we can start calibrating our MAF!!​
Step 3: MAF Calibration
This portion is really important to the drivability of your goblin, Go out and do some driving but make sure to have VCM scanner running. Take it easy though, be very gentle on the throttle and try not to make drastic throttle changes and keep the rpm relatively low as our fuel is going to be way off for the first few runs.​
Upon returning from your gentle drive make sure to save your log file. jump to the graph we created earlier, select the entire graph, right click and click copy. Jump back over to the VCM editor​
Update MAF Calibration:
Engine>Airflow>General>MAF Calibration>Airflow vs. Frequency​
Select your entire table, right click, select Paste Special>Multiply by % - Half​
Step 4: Repeat
Continue the drive then MAF calibration until the error reported is less than 5% across the entire graph up to about 6000 Hz. Each time you calibrate the MAF you can start revving the engine out further but continue to keep inputs smooth and do not go WOT.​
-Method 2: Fuel Trims vs. MAF Frequency
With this method you leave most tables enabled but disable dynamic airflow. I have been learning to tune under a well known tuner in the cobalt community and this is the method we have been using. However, I do not know or have an opinion on which method is better.​
Step 1: Scanner Setup
For this method of tuning we are going to be using two different graphs to measure our fuel trims vs. MAF frequency.​
Our first graph will monitor our STFT + LTFT vs. MAF frequency and is setup as shown:​
LTFT+STFT.PNG
*Note: The Values for the MAF Frequency were acquired by copying the axis from the MAF table in VCM editor
The second table we will be monitoring will use just the Long Term Fuel Trims like shown:
LTFT.PNG
Step 2: Fuel Trim MAF Calibration Setup
This version of MAF calibration only disables Dynamic airflow and allows the engine to work in closed loop to determine what fuel trims make it happy.
**Disable VE Tables**:
Engine>Airflow>Dynamic>Dynamic Airflow​
High RPM Disable -> 300 rpm​
High RPM Re-enable -> 200 rpm​
Setting these will disable the Volumetric Efficiency tables, By disabling these tables the car will not adjust fueling via calculations using cylinder air mass.
Step 3: MAF Calibration
This portion is really important to the drivability of your goblin, Go out and do some driving but make sure to have VCM scanner running. Take it easy though, be very gentle on the throttle and try not to make drastic throttle changes and keep the rpm relatively low as our fuel is going to be way off for the first few runs.​
Upon returning from your gentle drive make sure to save your log file. jump to the graph we created earlier, select the entire graph, right click and click copy. Jump back over to the VCM editor​
While doing our initial MAF tuning via fuel trims we will initially use the LTFT only graphs until we get close to the final product. Then we will start using our STFT + LTFT graph.​
Update MAF Calibration:
Engine>Airflow>General>MAF Calibration>Airflow vs. Frequency​
Select your entire table, right click, select Paste Special>Multiply by % - Half​
Step 4: Repeat
Continue the drive then MAF calibration until the error reported is less than 5% across the entire graph up to about 6000 Hz. Each time you calibrate the MAF you can start revving the engine out further but continue to keep inputs smooth and do not go WOT.​
I am far from an expert and have a lot to learn on tuning but I like to organize my thoughts when learning something new and figured I would share my findings. As I stated earlier if you see any errors in my documentation here make sure to let me know so I can update it!​
 
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