Project GD Subaru STI Part Three- Making More Power with Greddy and Cobb Tuning


After a pull Mitch noticed some knock count on the top end.  Mitch tunes to a knock count of zero so he removed a bit of timing from the spark map at top.  A few more pulls to fine tune things and our car was ready to rock.  We were amazed at how fast tuning could progress with the AccessPort’s emulation feature.

We were really amazed at the results, the first curve is our baseline, the second an average pull with the Greddy RS exhaust and the last pull is after our tuning.  You can see before and after boost curves and air fuel ratio plots.   You can see at best, our car gained an amazing 72 hp at around 6300 rpm!  Our car gained 48 hp at the power peak!  The power gains are nice, big, fat and across the board.  Bottom end torque got a nice gain as well.  The Greddy RS exhaust and Cobb Socal’s solid tuning have been a huge bang for the buck.  Our car feels like a completely different animal and is 2X as fun to drive.


Stay Tuned, we have some cool things coming for Project GD STI from Greddy, Cobb Tuning and Koyo.  We will work towards getting more reliable daily driver pump gas power and keeping things cool on the track.



Project Subaru STi

Read More about Project STI here!




Cobb Tuning

Cobb Tuning So Cal


KW Suspension

Mackin Industries Advan Wheels

Falken Tires

West End Alignment



PLX Devices – Kiwi Bluetooth

Palmer DashCommand



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