As soon as your Intake temps go above 150 the computer starts pulling timing, and the higher it goes the more timing it pulls. The dual pass heat exchanger allows me to run a little extra timing also and stay in the safe zone by helping to keep those intake temps down.
The stock ecu starts pulling timing at 101* ait's and over 200* engine temps. If you car's ait's probably are over 120* just driving on the street therefor it's already pulling close to 2 degrees even with the dual pass h/e.