Thread: Starting Hptuners

This thread is going to be dedicated to learning how to use hptuners. Now be aware you can blow up your are if you make changes to drastically. Tuning your car is your own responsibility, if you have questions ask, its easier to take a few min to ask a question than destroy your engine.

Hptuners help link:http://www.hptuners.com/forum/showthread.php?t=5058

First we will need to read your stock pcm. To do this open up the VCM editor program and click read vcm.


After you read the pcm follow the licensing instructions and then save the file as stock of what ever you want it to be called. After the file is saved open up the file and we can begin the retuning process.

First step is to get the view set up in the tuner so you can view all tables. The program is set up at first so you can only view some tables. We want to see them all.


After we have that changed, we can begin changing some of the basic tables you want. IE torque management speed limiter and tire size.

Lets start with the speed limiter and fan settings. Speed limiter set to what ever you want. If you have aftermarket wheels and tires with a differnet diameter than stock use an online size calculator to modify the tables in the speedo panel. Gear ratio leave the stock one in unless you have changed them during a trans swap.


Fan temps Go into system then fans. These are my settings for a 180* thermostat


Now we will move on to torque management settings. We will start with the engine tables for it go into engine than torque management and start in the general section.

RPM vs gear table

Vs gear table

Vs RPM table


Spark retard table set to 0 across the board.
Then injector disable table set to 0 across the board also.

Abuse table


Supercharger table


Now we will be moving into the transmission torque management tables. Go to torque management. In the tables I have boxed sent them all to 0. and that will remove the torque management for the transmission.


Once you have all that changed resave the file under a different name IE base tune.

Time to get the fuel trims dialed in. We will need to edit the pcm to disable Power enrichment during this time. To do that you go to engine-fuel control- power enrichment. Changes the boxed table to 100%. Note DO NOT GO WOT with this table set to 100 you will have no power enrichment and will chip pistons.

Save the file under a different name again and reflash the car.

Now its time to open up the vcm scanner program and create a custom config file for maf tuning.

Open up the scanner to the default imperial settings.


Now we are going to make some custom histograms to log what we want and make is easy to use. Starting with plotting LTFT's on to the maf table.
To do this you will have to go into the primary table. The primary table shows what sensor are being logged by the scanner.


We will need to add Maff hz to the table to be able to set up our custom histogram. To add it right click an open cell and click insert. Then go to engine-airflow-maf hz


Now we can go back to the histogram section and make a custom histogram to make maff tuning 100x easier.


Once that is open go to your first open slot to make a new histograms. Click the configure histogram button and then double click the first open slot. Then set your histogram up like this and click commit changes at the top of the page.


Save that config file and its time to go out to the car and get a good scan.

Go out to your car and connect the scanner. Note yours will not have any data yet, I still had a log opened while I took the snap shot.


We will need to reset the fuel trims before we start the car. To do this go to vcm controls-fuel and spark-reset fuel trims.


Once they are reset you can start the car and click start scanning.


Make sure your laptop has a fully charged battery and go for a 30 min drive. Do a variety or driving. Get as far into the throttle as you can with out seeing any knock. Keep and eye on the KR gauge on the main page. Once you get the 30 min of driving click stop scanning and save the log file as a name you can easily remember.

Now once you are back home we will open up the log file and see what we have.


Once the log file is open you will need to load all data into the histograms


Once the data is loaded look at your maff LTFT histogram. We will want to copy the numbers from there to paste them into the editor program.


Now open the editor program back up and go to engine-airflow-aflow vs freq


We will now use the paste specials to change the table with our LTFT numbers Click in the top left to select the whole table then right click paste special multi by half


Once that is gone you will see some spikes in your maf table they are bad and we need to smooth them. To do this we will use the smooth feature on hp tuners. Click it once to smooth out the table and resave your file under a new name at that point.


Now reflash the car with the new file.


Once you have the new file on the car. Open the scanner back up reset the fuel trims again and go for another drive. Keep doing this untill you get all your LTFT's within 5% of 0.

Once all of your fuel trims are locking with in 5% of 0 its time to do some Wot scans. Before you do them you need to re enable Power Enrichment. Do this in the power enrichment enable table I set mine to 30% across the board.

You want to set your commanded afr to these settings for a supercharged car.


Now its time to add to our maff tuning config to log afr against the maf. Now for WOT fueling tuning I 100% recommend a wide band 02 sensor. You spent the money for a tuner, might as well get the best tune you can and not half ass it. AEM, NGK, PLX all have good wideband sensors. There are also others on the market. I have a write up linked here on how to log your NGK AFX wide band with hptuners standard interface. http://www.grandprixforums.net/hooki...ner-19455.html Other sensor will require a different formula to convert the voltage to an af reading. If I find the formulas I will post them up.

After you have your custom pid to log your af its time to make another histogram. We will be plotting your A/f against the maf table. For WOT tuning we will be concerned with the 7000hz and up cells on the maf. So lets open the scanner and get to work. Open up your next open histogram to make a new one for maf WOT tuning. Make it look like this.

Now if you are using your factory narrow band 02 sensor instead of using wideband under the PID you will choose 02mv under the sensor option. Using a wideband will be 200x more accurate so that is what I recommend.

Once you have your histogram set up hook up to your car and test it out and make sure it is working right. If everything is reading right do a couple WOT runs rolling onto the throttle from a stop. Then save the data as we did before.

Once you are back home open up your log file and see what we have.

The numbers we are looking for here are mid 11s for a supercharged car or if you are using a narrow band the 940mv range. In that pic I am running very rich, I would need to pull some fueling by scaling the maf table in the editor. Small changes are the best. 2% at a time are ok if you are very far off like I am.

To add fuel you will need to add to the table by multiplying by 1.02, if you need to pull fuel you need to multiply by -1.02. Remember we are only scaling from 7000hz up in the maf table like so.

Now we do not want any spikes in the maf table so in the cells before 7000hz scale them so they will flow with the rest of the table.

Keep tweaking the maf table until you get your WOT fueling dialed in. Once it is all in the mid 11s it is time to move onto WOT timing.

Now that we Have our fueling down Its time to get our timing table figured out.

We will start by zeroing out the timing modifiers to make it easier to command timing. To do this you will need to zero out the following tables.


We will also copy the High Octane spark table over to the low Octane spark table.


Now Reflash your pcm with the new changes and go get a new WOT scan. After you get the scan open up your log and lets take a look at histogram 2 spark retard.


You want to see all zeros in that table. If you do you can go back into the high octane spark table and add 1* of timing in the .92 section like so.


After you add the degree dont forget to copy it to the low octane table like before. Reflash the car and get another scan, If you still dont knock add another degree untill you are running about 18-20* of timing. Now if you are knocking in the lower rpm you may have to scale your timing so you dont knock. Same applys to higher rpm. You dont want to run below about 15* tho. Once you add timing keep an eye on your fueling still, adding timing can cause you to run a little leaner and you may need to add some more fuel to stay in the mid 11s or 940mv range. After you get the timing set to the 18-20 mark its time to drop a pulley size.

Once you drop a pulley size you will need to retune the LTFTS and WOt fueling. Follow the same process as before. When drop a pulley and start to retune I would drop the WOT timing down to about 15* to be safe. Once you get everything dialed in start the spark tuning again.

Now with weather changes your fueling tables will also need to be changed. Cold air is denser than hot air so you will need fuel to counter act mother nature. You might not be able to run as small of pulley in the winter as you do in the summer. That is why an mps system is nice and you can have a few options to go with.

Now that your car is running like a raped ape on the track lets try to get some fuel mileage out of it. To do this we will add some timing into the cruise cells in the timing table.


Keeping adding timing untill you get some KR then Drop back about 3*. I also would not go over 40*.

If you are changing to larger fuel inectors you will need to scale your Injector table. To scale the injector table you take your new injector flow rate IE 65 devided by your stock flow rate IE 36 for stock gtp. so 65/36=1.81 You than multiply your injector flow rate table by that.


Now that will not 100 percent get them set right. You will need to redo your maf tune after changing injectors. To get your trims back in line.

E-85 tuning, pretty simple scale your injector table back by 30% (making the numbers smaller so the computer thinks they are flowing less and adds more fuel). Then do a few maf tunes and start adding timing.

Sticky when youz done?

Better be lol. So far I have like 5 hours in it.

Now convert the pics to Jpeg so you can embed the images

I could embed them, but I didnt want to rescale every one. So they will be hot linked for now. Once I get the info down I might resize and embed them.

Cool, I was just thinking it would be easier to see it all at once! Great write-up so far though!

Nope thats all you have to do, I would just get your tune down on pump gas first then scale for e-85 and do a maf tune.

About how long should it take to do everything?

First maf tune should take like 2 hours or so.

Awesome dude... Thanks!

after i make my hist. i go to scan and it pops up as unsupported still? :/

i am wondering if your method will work for 04+ in consideration to maf tuning...

Started this already... Once I set my injector table back to where it really should be my fuel trims were so far out I did the special paste but twice with the full number instead of half the second time. I did it just to get into the ballpark and it worked pretty well. Third time I did about the first 20 cells on full value multiply and then did the whole thing full again and its really close now. So anyone who is impatient like me can see if this will work for them too... Just don't forget to smooth the selection once or twice, and my trims started out at like 16 on the first part and gradually went down to like 10ish towards the other end.

Originally Posted by gtpsleeper

after i make my hist. i go to scan and it pops up as unsupported still? :/

I did that too... I had to add the maf hz back to the primary and it worked. I then saved the entire config so I can just load it anytime I need and never set it up.