[Karlot]

Hello. I know this is an old post however it is quite relevant to me. I just purchased my first sti that has a Cobb catted down pipe and SF intake with a stage 2 ots map. According to your post and Cobb (i spoke with them today), the risk with this setup is that the fuel system cant keep up and the car may run lean. Will this exclusively affect the performance of the car or can it cause actual damage? The car feels like it is running great. I appreciate the help.

you will want a pro tune, but the stock fuel system can handle anything you can throw at it with a stock turbo, assuming you are on pump gas.

 

[Karlot]

Cobb has gone through quite a few revisions of their staged ots maps and what was once a stage 2 is not at all the same as what is now a stage 2. (Green speed update, had a big effect on this.)
Old stage 2 OTS maps were offered for stock injectors/aftermarket DP.
New stage 2 ots maps are all setup for Cobb/ID1050x injectors and catted or oem DP.

Just the difference in injectors makes the 2 stage 2 ots maps NOT interchangeable.

Cobb Tuning Subaru updates aka Green Speed

Best thing to do is figure our exactly what mods are on/in the car and get a custom pro tune. If your hardware setup matches current ots offerings you can try to run those BUT for any EJ powered subi i would always recommend a custom tune using a wideband! (ots just isn't good enough imo).

Unless something is different in your country, the new stage 2 is for an oem downpipe. You can’t use the same map for oem and aftermarket downpipes.