Sniper Software and Firmware Updates

Posted by Chris Myer 04/24/18 2 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.

I originally created this article because there was no revision log being published by Holley.  Fortunately, that has changed, and a revision log can be downloaded here. Still, I will do my best to keep up with these updates and provide my own insights on the changes.  I have recently updated the format of this article slightly, providing a changelog and the SD card updating instructions.

Software / Firmware Inter-compatibility

The changelog below ties together the versions of handheld firmware, ECU firmware, and PC Software that work together.  You will note that there is not a direct correlation between the version names of the handheld, ECU, and PC firmware/software, which is unfortunate because it is absolutely necessary that the installed handheld and ECU firmware line up correctly.  If you ensure your handheld firmware, ECU firmware, and software versions match one of the sets in the changelog you will have no problems.  If you connect a older-version handheld with a newer-version 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.  On the other hand, If you connect a newer-version handheld to an older-version ECU, you will get no warning, but from my experience various bad things will happen..  Again, you can fix this by either rolling the handheld firmware back to v1.0 or updating the ECU firmware to 1.1.

Early versions of the software were more forgiving of firmware/software version mis-matches but once version 1.1 Build 3 was released it, too, required ECU firmware 1.1.6 or later. So better stick with the combinations shown below.


Handheld Firmware v 1.1.25 / ECU Firmware 1.1.14 / Software version 1.1 Build 3 (No Update):

This is the third firmware version in a row that works with the Version 1.1 Build 3 software. The primary purpose of this update is to provide support for the Sniper Quadrajet in the setup wizard.

Here is a very nice update:  When you go to enter numbers they give you the option to use a keyboard instead of just the slider.  Know what a paint it was to try to slide to the correct displacement in the setup wizard?  Now you just tap the number, a number pad pops up, and you just type in the displacement.

Also nice, this version can now show temperatures in celsius.  Pretty cool, eh Canadian friends?  Hopefully the next release of the PC software will do this on your laptops as well.  A Screen brightness feature is also added to File > Local Setup.  Finally, the Monitors > Monitor > "Misc." display has been renamed to "Vitals".  Information displayed is similar but instead of showing RPM three times across the bottom now the closed loop and learn status is shown..

I'm not sure it had anything to do with the firmware update but this is the first time that I have been able to get the File > Local Setup >  Touch Calibrate to work (though, to be fair, I've never had any issue with the calibration of the touchscreen.) 

Handheld Firmware v 1.1.20 / ECU Firmware 1.1.6 (No Update) / Software version 1.1 Build 3 (No Update):

Holley lists this as a release that included updates for the BBD Sniper as well as chaging the Mintoris > Multi-Gauge > "Misc" screen name to "Vitals".  However, on the one copy of the 1.1.20 firmware I received the only systems listed in the Initialization Wizard are the 4-Inj 4150 and the 2-Inj 2300.  I think this may have been a "whoops" and was immediately superseded by 1.1.25.  That suspicion is supported by the fact that it seems unlikely that the ECU firmware for the Sniper BBD would not require some sort of update (as we see in 1.1.25.)

Handheld Firmware v 1.1.15 / ECU Firmware 1.1.6 / Software version 1.1 Build 3:

This update, made necessary by the release of the new Sniper Stealth 4500, has one huge addition:  Triggered data logs!  For a hopeless geek like me I've been waiting to see this on the Sniper.  The HP and Dominator ECU's have had this forever.

Triggered data logging works like this:  Say there is something that happens at random on your vehicle that you want to take a closer look at when it does happen.  But that event is not courteous enough to say, "excuse me, Sniper operator, I'm about to occur so you need to go into Logging and start a data log."  It just happens.  Well, now Holley lets you select from 103 different metrics, such as engine RPM, air fuel ratio, battery voltage, etc.  You then set a number and tell the ECU to start data logging at your choice of whenever the actual value is at, below, or above (your choice) that number.  How cool is that?

Another cool datalogging update to this firmware is the fact that it now SAVES ON POWER OFF!  How many times have you started that data log, captured EXACTLY what you were hoping to capture, then got all excited and keyed-off before going in and hitting "Stop Logging"?  No longer an issue--the data log is saved!

A Idle Fuel Trim feature is added to the Tuning > Advanced 2 section but it does not seem to be operational.  Maybe a "Coming Soon"?

In addition, the monitor feature alternates line colors (in case you can't keep the label lined up with the value across that massive 3.5-in screen.)  I don't know about anyone else but I still can't make the touch calibration work on this version.  Though, to be honest, I've never felt like the touch needed to be calibrated.

Handheld Firmware v 1.1.7 / ECU Firmware 1.1.1 / Software version 1.1 Build 2:

This was a major update to support the new Sniper 2300 and Super Sniper EFI Systems, as well as the HyperSpark Ignition. 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

Handheld Firmware v 1.0.9 / ECU Firmware 1.0.9 / Software version 1.0 Build 4:

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.

Updating your Handheld and ECU Firmware

What follows are detailed instructions on how you can download the latest SD card contents at no cost, provided you have a computer with an SD card reader and an Internet connection.  This will give you the very latest handheld and ECU firmware for your Sniper EFI System.  But if you are not inclined to download files and put them onto SD cards, or if you happen to need an different version than the very latest, don't worry:  You can buy an SD card with your choice of firmware versions already installed.  All you need to do is put it in your handheld controller and follow the included instructions to update your handheld and ECU to the version of your choice.

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.

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. Early versions of the SD card contents included an instructions file.  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. Backup Your Current Configuration!

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.

When the configuration is cleared by the firmware update 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, and when you restore the configuration those warnings should be gone.  Even without a configuration 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 even with a good configuration 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 3. 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 (v 1.0.9)  Screen shot displaying Sniper ECU firmware update process (v 1.1.7)  Screen shot displaying Sniper ECU firmware update process (v 1.1.15)

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 4. 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.

Step 5. Restore Your Configuration

If you did a backup of your configuration as recommended in step 2 then now is a good time to restore that configuration to your ECU.  Use the handheld device to navigate to Files > Global Configs, find the configuration file that you just saved, and upload it to your ECU.  You should be all set.

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.  Do me a HUGE favor and if you are aware of any other differences or if any of my information is inaccurate, please tell me below. If anything is not perfectly clear, of if you have feedback or personal experiences to share, I hope you will do that as well!  :-)

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

2 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

06/23/18, 11:34:45 PM

Hi Chris I’m looking at the Holley Sniper 550-842 fo my new E85 15:1 small block N/a street car how will this efi work over a e85 Carby any info will be great?

Chris Myer:
06/27/18, 03:19:37 PM

Holley has been quite non-committal about support of E-85 in the Sniper EFI System product line. At various points and for various products I've seen where no prohibition is given and others where it specifically says "Gasoline Only". Holley's website page on the 550-842 is one example of "Gasoline Only". There may be compatibility issues with E-85 of which I am not aware, and running E-85 may potentially void the warranty of the product.

Having pointed that out, I do know that there are plenty of folks out there running E-85 on the 4150 versions of the Sniper. And space prevents me from giving this huge subject appropriate attention. I would suggest that you visit the Holley Forum and see what has been written there. If you put the following into Google then you will get a number of specific posts that should be helpful: sniper E85

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