Two Step Performance

Stage 1 to Stage One+ UPGRADE for the 2017-2020 Si (Existing Stage 1 Owners Only)


  • Sale
  • $67.49
  • Regular price $149.99

Customer Reviews

Based on 56 reviews
exit2302_fc1 (Westfield, US)
Ran at the track!

Great tune. Pulled harder than the original stage 1 tune. Helped improve my lap times. At Palmer, running in third gear in the upper rpm range most of the time, and this is where I felt the improvement.

Brandon (Saint Albans, US)
Great tune!

Started out with the TSP Stage 1 and upgraded to the 1+ to get a little more power mid/top end power. Aboslutely loving it! Another great tune from TSP

Osbaldo (Kansas City, US)
TSP upgrade tune

I had the TSP 1 tune for about six months and was great. Found out about the upgrade so i have it a shot and it feels a lot better. The first one was great the upgrade is even greater. I like how it reduced the vibration from the rmm. Overall great tune made the car run smoother and feels faster!

Matthew Ramirez (Los Angeles, US)
Same great tune, made even better

Feels smoother to drive, and the raised idle reduces vibration with an upgraded rear mount. Not to mention, it gives the car even MORE pep in its step.

Brock Weaver (Santa Clara, US)
More than I bargained for

May not seen like much additional power on paper but absolutely made a difference in feel

Shawn Green (Maineville, US)
Great OTS tune

The stage one + tune is a great addition of power and revisions from the stage one tune. One of the things that annoyed me about the stage one, especially if you have an aftermarket rear motor mount that has been fixed in this tune is the slight increase in RPM when idling. Definitely worth the upgrade from the original stage one!

Existing TSP Stage 1 Si tune owners can use this product listing to upgrade to our new Stage One+ tune at a discounted rate! This is eligible to anyone that has purchased the TSP Stage 1 tune directly from us, either as a standalone tune or with a KTuner unit. This will be verified before the order is filled.




Are you looking for the highest level of safe power output from your 2017+ Civic Si? Look no further!

Two Step Performance continues to partner with Derek Robinson to offer an even more powerful tune for the 2017+ Si. Full details are as follows:

234whp / 279tq - TSP Stage 1 Tune
248whp / 290tq - TSP Stage One+ Tune

All testing was completed on a stock 2020 Civic Si running 93 octane fuel. Tune features include:

  • Numerous fuel, ignition, turbo response, throttle response changes.
  • More aggressive tuning strategy compared to original TSP Stage 1, allowing for more midrange and top-end power.
  • Increased warm idle speed to eliminate vibration from aftermarket mounts.
  • Standard MAF, PRL Motorsports "Race MAF", and 27Won Performance "Race MAF" support (select appropriate option)
  • WOT shifting enabled. (Set to 5000RPM)
  • Adjustable launch control enabled.
  • "Rev hang" disabled with soft throttle padding (user adjustable)
  • Several tweaks to smooth the feel between gear shifts.
  • All disables / monitors are able to be adjusted by the end user.
  • Quick Boost By Gear is able to be adjusted by the end user.
  • On-the-fly boost map switching active for normal and "Sport" modes. (see below)
  • Throttle Responsiveness & Throttle Padding Settings are allowed to be adjusted by the end user so that the overall feel can be aggressive or more toned down, as desired. 

Map 1: Factory boost levels and turbocharger response.
Map 2: 19psi normal, 21psi "Sport" mode, Improved Turbocharger Response 
Map 3: 26psi normal & "Sport" mode, Fastest Turbocharger Response


Factory boost level in "Map 1" allows for easy "valet" mode when the KTuner unit is unplugged from the car!

93+ octane REQUIRED. Use of lower grade fuels is NOT tolerated, and will result in power loss.

  • 100oct race gasoline is suitable, as long as it does not contain lead.
  • The calibration will support up to about 15% ethanol content if necessary to increase knock resistance. For example, you can blend approximately 1 gallon of E85 with 91 octane to achieve the knock resistance required to safely and effectively use this tune.

Upgraded clutch recommended.

Suitable for use with the factory intake or a QUALITY aftermarket intake that keep fuel trims in check such as the PRL Motorsports Cobra. Aftermarket downpipes are also fine. Mods such as this are expected to add power that is not accounted for in our dyno testing.

In addition to standard sized intakes, the PRL Race MAF Cobra & Short Ram intakes as well as the 27Won Race MAF intake are supported. Please select the appropriate option for your intake when ordering. Need to make a change later down the road? Take advantage of our File Conversion Service.

*Tune orders placed during business hours are typically fulfilled via email the same day. Orders outside of business hours are filled the following business day. FlashPro tune orders may be slightly delayed due to the process required to build your custom file.*

Please verify that your ECU is supported via our TSP Tune Compatibility List prior to purchase.

This tune is for the 2017+ Civic Si only. Please be sure you are purchasing the correct tune for your vehicle because digitally delivered items are non-refundable. (If you buy this for your 2016 Civic LX, it won't work, and we cannot offer a refund.)

Click here for our installation guide.