I have just ordered a DP and headers, what should my next mod be to increase power? WIthout getting a larger Turbo. Cobb AP or FMIC?

 

You need some sort of Engine Management.

 

+1. I would invest into an AP. Once you have that you can get a protune and get even more HP out of the mods you have/ordered.

 

dont install the dp and headers without the ap. this can cause major problems. and an fmic is not needed for a long time... not until major larger turbo.

 

DO NOT INSTALL YOUR PARTS UNLESS YOU GET EM!!!! you have the 07 and they are already sensitive to mods with the EM. Buy the AP then install your parts and go get tuned. you will be very pleased with the power after that

 

cobb ap with a protune.

 

While I see a TON of people talking about the Cobb AP like it is the end-all be-all form of Engine Management it may not be the BEST solution for YOUR needs. It is Plug-and-Play, but I definitely recommend consulting with a local tuner and researching the different forms of Engine Management. You may find that you like to do the tuning yourself in which case the AP could possibly be the WORST solution to meet your needs.

I am not saying the AP is bad by any means, just saying that it might not fit your personal needs for an EM. Yes, you should get EM. Should you get an AP, depends on what you need, want or are willing to pay for EM.

 

+1 Very good investment.

 

I agree with everyone else, definitely get a tune. The 2007 STi is known to have some ECU issues, so I would absolutely not put those parts put on your car unless you have a tune for them (preferably a custom tune).

Do some searches on NASIOC.com in the 2.5L forum for "low compression cylinder 4".