Category Archives: Tech

New Facebook Group: Subaru Info Tech Club

Hi Everyone,

This past year has been extremely busy. So much has happened with the subie. I can’t wait to share all the new installs such as the Group N engine mounts and transmission mount, steering rack brace, bushings, and more. I hope to get the images in order before I can post them.

My good friend Daniel also picked up a 2015 Launch Edition STI. I’ve been trying to help him install a new turboback system from Nameless.

Last but not least for now, I created a Subaru Info Tech Club group on Facebook. I hope to get more people in the IT and Engineering industries who owns subarus to come together to share daily problems, current projects, and or subie related. If you are in the industry, please click on the link below and join the group. Don’t forget to suscribe to this blog as well. Thank you.




2015 Subaru STi Dyno’ed at Higher Numbers??

I recently came across an interesting article on IWSTI in which the community was discussing how the new 2015 SUbaru STi has more wheel horse power on recent dynos; despite the advertised 305 crank horse power by Subaru in past years. The previous generation also labeled as “GR” or “GV” models were only dyno’ed at around 220 – 240 whp.

Some owners of the new 2015 STi were fortunate and kind enough to
get some base runs on the dyno to show what numbers the same EJ engine is made of. Granted, this is the same engine from previous models, what could have possibly changed?

One user on IWSTI had the Subaru STi dyno’ed at 262whp. That is an increase of 20+whp !!


Hold on a second. Before I go any further, I’m sure some of you will say “not every dyno is the same” and that is true because of a few factors.

  • Outside temperatures – The entire engine bay thrives on cooler air. If you perform a dyno on a hot summer day, you’ll get lower numbers.
  • Different dyno model – Every dyno runs differently especially on Mustang Dynos, Dynojet, etc.
  • Type of gas used – The type of gas used will affect performance depending on where you live.
  • Sea Level – Certain altitudes in the U.S. can produce lower numbers
  • The car itself – Even though all the cars are exactly the same off the production line; it performs differently in every driver’s hands. Automatically, it makes each car unique.

It can be confirmed with the tuners as well that not every car is the same especially with the above factors.

Airboy Tuning kept a lot of baseline logs of STi cars from 2008 – 2013. They ranged anywhere from 217 – 230whp. It can be seen from the below pic.


Perrin Performance was also able to get their hands on a 2015 Subaru STi. They were able to get a base comparison with the previous generation 2008 STi. Surprisingly, something changed in the engine that gave the 2015 STi 20whp more than previous versions. What Perrin claimed is that the 20whp came in at the mid range power band which may in turn result in longer turbo spool or boost comes on slower at about 4500-5500RPM.


Perrin Performance Source

Maybe Subaru did something right for a change. They finally listened to the community and re-tuned the engine with an ECU map that is still stock but more aggressive. In the aftermarket world, that pretty much puts the car into a Stage 1 category.

When Subaru hosted their pre-launch presentation on the new generation, they did talk about the ECU being tuned for responsiveness. Could this be the reason for the horse power increase?

Subaru ECU Retune on the 2015 STi
Subaru ECU Retune on the 2015 STi

You can watch the full hour here if you’re interested.

It also makes you wonder if that is the reason why Subaru decided to keep the EJ engine the same all these years. All they have to do in every generation is tweak the ECU map to drag out sales. From a business point of view, it makes sense  until sales drop and the competition comes out with newer and better parts.

Only time will tell.

Let me know your thoughts in the reply section.

– Harry