• MON-FRI 8-6

Dyno Tuning


JM Automotive is the fastest growing Subaru performance shop in Minnesota. We sell and install performance parts, do full engine overhauls, performance builds, and offer tuning to go with it!

Our full-time tuner Devin has been tuning Subarus and other makes for a number of years and has experience with both open source and AccessPort tuning. For more information on tuning, you can call us at 763-316-5882 or email us at tuning@jmautomn.com.

We have a lot of information about tuning and modifying your car; before doing so, please check out our Mod Guides and Why E85 is so Popular.

If you are looking for build advice and to purchase some parts, JM is the 1 stop shop to buy parts, get them installed, and get your car tuned. Contact us today to begin your build – no build is too big or too small for our experts. More information can be found by visiting our parts page and filling out the form.

We tune with the following programs:

  • Cobb Accessport (Subaru, Mitsubishi Evo X)
  • Opensource/ECU flash (Subaru and Mitsubishi)
  • Openflash tablet (BRZ and FRS)
  • EcuTek (BRZ and FRS)
  • Project Lambda (1999-2002 Impreza / Forester, 2000-2001 Legacy)
  • Megasquirt
  • Haltech
  • Motorsports Electronics

If you have a different tuning software call and see if we can help you out with it.

Note: A Cobb Accessport is require for tuning the following vehicles: 15+ Subaru WRXs & 14+ Subaru Forester XTs

We are here to help!

There is nothing worse than getting your car tuned and not making the power you were hoping for all because the fuel pump or injectors you just purchased are too small or you end up with massive turbo lag because the turbo you choose is too large for the power you want.

Feel free to contact us and we can help guide you through picking all the parts for your build. We do this all day every day and have a lot of experience with aftermarket parts and can help you decide what turbo, injectors, fuel pump and many other parts to get the most out of your tune and have a great driving car for the purpose you plan to use it for. We also are parts vendors for pretty much every major performance parts brand out there and price match any listed price online from authorized dealers.

Contact us for your build advice, parts purchases, and part installations.

*Due to the high volume of inquiries on build advice we can only offer this to customers who purchase their parts through us. Time is money and knowledge isn’t free. We price match any online price. Your parts supplier should be able to give you the proper advice to purchase the proven parts for your goals and plan of use. If your parts supplier can’t give you any direct knowledge of the part besides what’s listed in the description it might be time to find a different parts vendor. If you are looking to purchase parts through us, we will gladly put a build list together for you to meet your goals and make sure you have all the best dyno proven parts.

Before modifying your vehicle, please understand the following:

  • Modifications and tuning can and most likely will void any vehicle warranty you have
  • Certain modifications and tuning are not street legal and designed for track use only
  • We are not liable for any modifications purchased from us, installed by us, or any vehicles tuned by us. Research before you modify your car and modify your car at your own risk
  • 2013-14 WRX’s have a high failure rate and have class action lawsuits against Subaru. The factory Subaru engines have some known issues, but in these years the failure rates are even higher than others, stock or modified.

Emissions Compliance Up-Dates:

Times are changing. To keep the aftermarket performance industry alive and following Cobb’s “Project Green Speed”, we do not disable any check engine lights while Tuning. That means we won’t tune your car if you have a Catless Downpipe/J-Pipe , TGV, or EGR Deletes. If you have any questions or are unsure if we can tune your car, please contact us at tuning@jmautomn.com

We CAN still tune Upgraded Turbos, Fuel Injectors, Fuel Pumps, Intercoolers and more. These updates really only remove the ability to turn off check engine lights and flex fuel. We already off a new version of flex fuel, that works with the latest Cobb Green Speed updates, for the 2015+ WRX and more models are soon to follow! Check our Blog for the latest updates.

Cobb Tuning Project Green Speed Updates.

Project Green Speed 3/31/2021

Project Green Speed update 1/31/2022

Project Green Speed update 3/16/2022

Project Green Speed update 4/18/2022 – Removal of Flex Fuel & DTC suppression

Project Green Speed FAQ for 4/18/2022 update


Check out our pricing list for the most common vehicles, dual tunes, dyno rental, and more.

Pre-Tune Checklist

Check out our pre-tune checklist to make sure you and your car are ready for your scheduled tune.


Get all you need to know on modifying your 2015+ WRX or STI with first-hand experience from JM.

Ethanol Calculator

Use our ethanol calculator to easily calculate ethanol percentage in your fuel mix.

Pre-Tune Forms

Click below to fill out your pre-tune form to help us get the most out of your upcoming tune.

Pre-Tune Waivers

Save time and click below to sign your tune waiver ahead of your schedule tuning session.

Frequently Asked Questions

Below you will some frequently asked questions relating to tuning. If you have any additional questions, feel free to reach out by calling us at (763) 316-5882 or via email.

Sometimes knock is also called detonation. Detonation is characterized by the air/fuel mixture spontaneously igniting during the compression stroke. The force of this early, unintended explosion is counter to the direction of the piston and results in a sharp increase in cylinder pressure.

Read more at Cobb Tuning

Thanks to the power of the AccessPORT, it’s now easier than ever to gain unparalleled insight into the current status of your engine’s tune and running condition at any given time.

Read more at Cobb Tuning

When trying to diagnose driveability problems or assessing how well a new tune is working with the vehicle datalogging can be an invaluable tool.

Read more at Cobb Tuning

  1. With the Accessport installed navigate to the “gauges” menu.
  2. If it’s the first time you’ve gone to the gauge menu of the Accessport it will prompt you to ask how many monitors you want to display. The selection can be updated later in the Gauge Setup menu.
  3. From the main gauge display, you can simply hit the center button on the Accessport in order to start logging. If you haven’t pre-selected anything there are default parameters that will be logged which are typically the ones COBB Customer Support will ask you for. Note that the Accessport will show “logging” at the top of the screen and at the bottom will let you know the logging rate.
  4. In order to stop logging, you’ll need to hit the center button on the Accessport again.

Read more at Cobb Tuning

You can find the serial number to of your Accessport V3 underneath the faceplate of the device or within the software. The serial number can be found in the software by selecting “Help” at the top, then selecting “About Accessport”, lastly scroll down until you see “Serial Number Sticker”.

Read more at Cobb Tuning

Garrett Turbo describe boost creep as the following:

“Boost creep is a condition of rising boost levels past what the predetermined level has been set at. Boost creep is caused by a fully opened Wastegate(s) not being able to flow enough exhaust to bypass the housing via the Wastegate(s) itself. For example, if your boost is set to 12psi, and you go into full boost, you will see a quick rise to 12 or 13psi, but as the rpm’s increase, the boost levels also increase beyond what the boost controller or stock settings were. Boost creep is typically more pronounced at higher rpm’s since there is more exhaust flow present for the Wastegate(s) to bypass. Effective methods of avoiding or eliminating boost creep include porting the internal Wastegate(s) opening to allow more airflow out of the turbine, or to use an external Wastegate(s).”

Read more at Cobb Tuning

Have Questions? Call Today!
(763) 316-5882