Sniper Software and Firmware Updates

Posted by Chris Myer 04/24/18 1 Comment(s) Holley Sniper EFI Instruction,

Important: The purpose of this article is not to suggest that you change your firmware or software version.  After over 30 years in software and electrical engineering, I have learned never to upgrade any sort of software without good reason.  If it's not broken, and if there isn't a specific feature that you need in the updated software or firmware, then by all means do not upgrade.  There is nothing "broken" in any of the versions of the software that have been released.  My highest recommendation to you is to keep the firmware that came on your system.  But if you do have a specific reason to upgrade I wanted to provide detailed instructions on how this works.

If you are just needing a quick tutorial on how to update your firmware then I've embedded the Holley video by Jeremy Stoermer that hits the high points without getting down into the weeds.  Find that at the bottom of this article.  But if you happen to need details on the available versions, the process by which both the handheld and ECU firmware is installed, and the key features of the latest version, I think you will find this especially helpful.

As of this writing,I am aware of at least three releases of Sniper ECI Handheld Firmware, three releases of Sniper EFI ECU Firmware, and two releases of the Sniper EFI Software:  As the version numbering implies there certainly must have been others, but to my knowledge these were the only public releases.

Sniper EFI Handheld Firmware.

The three releases of the Sniper EFI Handheld Firmware are version 1.0.6, 1.0.9 and 1.1.7.  They are saved in two places on the SD card:  One copy is in the root directory (/) and, in the case of the most recent two, a second copy at either

  • /HOLLEY/FW0100/tslcd35st_sniper_fw_01_00_0090.fwu (version 1.0.9) or
  • /HOLLEY/FW0101/tslcd35st_sniper_fw_01_01_0070.fwu (version 1.1.7)

depending on the version you have.  You can view the firmware version installed on your handheld by using the handheld display to navigate from the home screen File > Local Setup > Local Info.  You will see one of the following:

Screen shot displaying Sniper Handheld firmware version (1.0.9)  Screen shot displaying Sniper Handheld firmware version (1.1.7)

Sniper EFI ECU Firmware

The three releases of the Sniper EFI ECU Firmware are version 1.0.4, 1.0.9 and 1.1.1. The most recent two are saved in the SD card contents as either:

  • /HOLLEY/FW0100/SNIPER_01000090.eep (version 1.0.9) or
  • /HOLLEY/FW0101/SNIPER_01010000.eep (version 1.1.1).

depending on the version you have.  You can view the version installed on your Sniper EFI ECU by using the handheld display to navigate from the home screen to File > ECU HW/FW. You will see one of the following:

Screen shot displaying Sniper ECU firmware version (1.0.9)  Screen shot displaying Sniper ECU firmware version (1.1.1)

Sniper EFI Software

There are two releases of the Sniper EFI Software for the PC: version 1.0 Build 4 and version 1.1 Build 2.  If you have the Sniper EFI Software installed on your computer you can find out what version by opening the software on your PC, left-clicking on "Help" (not the one with the '?'), and then left-clicking on "About Holley Sniper EFI".  You will find the version and build information there.

Software / Firmware Inter-compatibility

You will note that there is not a direct correlation between the version names of the handheld, ECU, and PC firmware/software but don't let that throw you off.  The bottom line is that the Sniper ECU Firmware and the Sniper Handheld Firmware must be of the same version (1.0.x or 1.1.x) to operate together.  If you connect a v1.0 handheld with a v1.1 ECU, a bold warning is shown on the handheld telling you "Connected ECU version is not supported by this device.  Firmware upgrade is required."  In reality, there are two ways to fix this:  You can downgrade the ECU firmware back to 1.0 or upgrade the handheld firmware.  If you connect a v1.1 handheld to a v1.0 ECU, you will get no warning.  Everything will seem to work correctly.  The only thing I know that will not work is the setup wizard.  It will get confused trying to find the base configuration file in the /HOLLEY/FW0100 directory and fail.  Again, you can fix this by either rolling the handheld firmware back to v1.0 or updating the ECU firmware to 1.1.

Sniper EFI Software for the PC will work fine with either the v1.0 or v1.1 ECU/Handheld firmware. 

Updating your Handheld and ECU Firmware

It may be reassuring to know that as part of the investigation for this article I was able to upgrade and downgrade back and forth between the v1.0 and v1.1 with no problem. Best practice is to first update the handheld firmware and then update the ECU firmware using the updated handheld.  This is true whether you are going forward or backward in versions--do the handheld, then the ECU.

One important warning.  You can turm a piece of hardware into a worthless brick if you interrupt the firmware updating process before it is completed.  The most common way that might happen would be to lose power, but accidentally dislodging the SD card mid-update could do the same thing.  So don't do that.

Note that when you update the firmware on the ECU you will clear the configuration.  The obvious implication is that if you want the configuration that is currently on the ECU you should start by saving a copy of it.  You can do this by using the handheld to navigate to Files > Global Configs, selecting "Download from ECU", then selecting "Save GCF as..."  The configuration file will be saved to the /HOLLEY/FW0101/Saved GCF/ folder with that name.

A less obvious implication of the configuration being cleared by the firmware update is that all of the settings under tuning with display as "ReadErr" or "notAvail".  This is what is normally displayed when there is no configuration in the ECU.  The ECU itself should still be able to read and display the sensors, so if you navigate to Home > Multi-Gauge > Monitor > Sensors you should be able to see valid values on all of the sensors.  If you ever find yourself in a situation where you are getting read errors on the sensors there is a potential fix for that.  Remove the fuse from the Sniper ECU for 20 minutes.  Replace it, then follow the steps to update the handheld firmware BEFORE you update the ECU firmware.  This should put you back in business.

Step 1. Preparing the SD Card

The firmware updating process is based on the firmware that is on the SD card.  For that reason, the key to updating the Sniper EFI Handheld and ECU Firmware is to have the correct files in the correct directories on the SD card.  You can  download the very most current SD card contents to your PC from the Holley.Com website.  Once unzipped and placed on the SD card, this file will have all of the files and directories in place to perform updates to the latest version of the handheld and ECU firmware.

Alternatively, I have saved this copy of the last v1.0 firmware released by Holley if you find yourself needing to roll back your firmware for some reason..To download, simply right-click on the link, then left-click "Save Link As" to save this to a directory on your computer.

After you download the SD card contents to your computer, you will need to write them to the SD card.  Follow these steps:

1. Save the current contents of your existing SD card.  Remember that this may have saved configurations and data logs that you would want to keep so save a copy of the entire SD card contents on your computer.

2. Erase the entire contents of the SD card.

3. Unzip the zipped file you downloaded to your computer.

4. Copy the contents of the unzipped folder onto the SD car.  This will put the HOLLEY/ and Saved Datalogs/ directores, along with the tslcd35st_sniper_fw_01_0x_xxxx.fwu firmware update file right at the root directory of the SD card.

5. Holley recommends deleting the instructions.pdf file from the SD card.  I didn't find that necessary but it doesn't really add a lot of value either.

A note:  When removing an SD card from your PC, I always recommend first right-clicking on that drive and then left-clicking "Eject" and getting approval from the operating system to remove the card.  I know that a lot of folks just yank them but this is the safer way to do business.

Step 2. Updating the Handheld Firmware

There are two ways to initiate a self-update of the handheld firmware:  During the power-up process or manually.

Upon power-up, the handheld looks for a .fwu (firmware update) file at the root of the SD card directory.  This is the case when you follow the SD card preparation results above.  If one is found then it runs that firmware update.  When the firmware update is completed, the .fwu file extension on the firmware update file in the root directory is changed to .--- and the user is prompted to "Remove SD, reboot device".  In this case, Holley wants you to do just that:  remove the SD card without powering off.  Removing the SD card will initiate a reboot.  The handheld will display the text you see in the images below.  When that completes just put your SD card back in place.  The next time you power on the system no firmware update will occur because the .fwu extension was changed to .--- in this update process.

Screen shot displaying Sniper ECU firmware update process (1.0.9)  Screen shot displaying Sniper ECU firmware update process (1.1.1)

The difference in the manual update process is that no .fwu file needs to be loaded on the root of the SD card directory.  It turns out that Holley put a second copy of the .fwu file into the /HOLLEY/FW0101 (/HOLLEY/FW0100) directory.  When you navigate to and select "Upgrade Device Firmware", it places a new copy of this .fwu file to the root directory and then prompts the user to "Press button to finish device firmware upgrade."  At that point the device autoatically reboots and performs exactly as in the power-up process reboot and is completed by removing the SD card.

Step 3. Updating the ECU Firmware

Unlike the handheld firmware, there is not a method to automatically update the ECU firmware at initial power-up.  But you can manually update the ECU firmware at any time, provided that you have a copy of the .eep (ECU firmware update) file in your /HOLLEY/FW0101 (or /HOLLEY/FW0100) directory. Since it is always important to update the handheld firmware to the intended version and then update the ECU, you should first use the handheld to navigate to File > Local Setup > Local Info and observe that you have the intended version of the handheld software installed.  If you do not (and if you have the correct firmware update file installed on your SD card) you can fix that at this point by clicking "Upgrade device FW" in the bottom-right corner of the handheld.

Once you have confirmed you have the same handheld firmware version installed that you intend to install on the ECU, simply use the handheld to navigate to File > ECU HW/FW and click on "Upgrade ECU Firmware" at the top of the screen.  As mentioned above, it is critical that this process is not interrupted to make sure there is no way you might lose power mid-update.

Upgrade Features

Handheld Firmware v 1.0.9 / ECU Firmware 1.0.9:

I did not do a side-by-side compariton with handheld firmware v 1.0.6 / ECU firmware 1.0.4.  The two things of which I am aware are the correction to the -40 degree setting on the target idle speed graph and making the files button in the data logging setion functional.  Neither of these are especialy vexing problems but nice to have fixed.  If you are aware of other changes please let me know.

Handheld Firmware v 1.1.7 / ECU Firmware 1.1.1:

This was a major update to support the new Sniper 2300 and Super Sniper EFI Systems. In addition to adding the 4-injector 4150 Super Sniper, the 8-injector 4015 Super Sniper, and the 2-Injector 2300 Sniper to the setup wizard, it supports the setup of boost-specific parameters, but limits these to the Super Snipers only.  Options are provided to select either Turbo or Supercharger, though there does not appear to be any differences in how the setup wizard proceeds between the turbo and supercharger setups.  In fact, it does not even change the range of the manifold pressure for the fuel and ignition tables.

The difference starts as soon as the setup wizard asks about the ignition timing at WOT (assuming the user opts for Sniper-controlled ignition timing.  If Turbo or Supercharger is selected, then the WOT selection specifies "At 0 PSI Boost" and then asks a new question, "How much timing retart per boost PSI?" and then asks how much to retard the timing per pound of boost.  Very nice!

But then it asks an unexpected question:  "Target AFR at 0 PSI Boost?"  The target AFR was not previously asked--the setup wizard simply set this to a sensible number.  Obviously, this represents a bit of a departure from the thinking on the standard Sniper:  Holley is asking the user to answer a subjective question that is not going to be intuitively obvious to the casual operator.  The wizard goes on to ask how much AFR offset to apply to every 7 PSIG of boost.  Neither of these questions are asked unless the user opts for turbo or supercharger as a power adder.

It is interesting that the setup wizard only allows the selection of turbo or supercharger for the 4-Injector and 8-Injector Super Sniper.  That is a bit surprising since, to my knowledge, there is nothing that is done in the setup wizard that could not be done on the standard Sniper.  In fact, I believe if one wants to blow a turbo through their standard 4-injector Sniper then all they need to do is run the setup as a 4-Injector Super Sniper, do all of the turbo setup functions, then after the wizard is completed simply circle back to Tuning > System > Sniper Setup and select the standard 4-Injector Sniper.

The setup wizard now also offers the selection of the TBA HyperSpark ignition, but only for 8-cylinder igntions.  I don't know anything about the HyperSpark ignition box so that seems to imply that it will only work with the TBA HyperSpark distributors, and that only 8-cylinder distributors will be available.  Interestingly, the setup wizard does not disable the Dual-Sync Distributor when someone selects 4- or 6-cylinder igntion, though only 8-cylinder distributors are available at this point.

Other changes:

  • Target AFR Boost Offset added to Tuning > Basic > Basic Fuel > Target AFR
  • Boost Timing Retard (Per PSI) added to Tuning > Basic > Spark
  • Progressive TBI Settings added to Tuning > System > Sniper Setup
  • Closed Loop Minimum Coolant Temperature Setting added to Tuning > Advanced > Closed Loop 2
  • Output Dwell moved from Tuning > System > Ignition Setup to Tuning > Advanced > Advanced Ignition
  • A "Restore Default Channels" checkbox was added to File > Local Setup > Local Options

Final Thoughts

You can switch back and forth between firmware versions.  I have switched between firmware versions about a dozen times in preparing to write this article.  Always remember when moving between versions to change to the new version on the handheld firmware first, then change the ECU firmware to match.

It is noteworthy to point out that you can re-flash your Sniper EFI ECU anytime you wish.  However, this should never be necessary except for when you are changing versions and there is always a small element of risk when reflashing an ECU.  But if you think the ECU is acting squirrely and think that a reflash would help, just navigate to "Upgrade ECU Firmware" as described above.  Contrary to the name on the button, unless you put a new version of the ECU firmware on the SD card, each additional time this button is pressed will simply result in the ECU being reflashed with the same version of the firmware that is on the SD card.

In sincerely hope that this has been helpful.  I've tried to find a balance between adequate instruction and readable brevity.  If anything is not perfectly clear, of if you have feedback or personal experiences to share, I hope you will do that below!  :-)

Join the discussion below or click here to read more articles from Chris about the Sniper EFI System!

1 Comment(s)

30 Rat:
05/16/18, 02:58:19 PM,

Excellent write up, extremely helpful. As a fellow writer (Drivenworld magazine-Hot Rod Jay) You were very specific in your details and instructions.... great job!

Chris Myer:
05/17/18, 12:03:07 PM

Thanks for the compliment! I should in turn thank Mrs. Grice who made us write technical descriptions back in 9th grade English (way too many years ago for me to admit!) Imagine asking kids that age to do something like that now. :-O

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