Originally Posted by watchunglava
ive accually allready bought the jeff hartman book and have been reading it . i ve also been on the opensource forums and have been trying to learn , but im such a noob at ecu tuning . im more of like ohh my water pump is shot let me fix it and upgrade it while im at it . but looking at some of the dynos of tuned 07 2.5i's man thats some untapped free power . i realize that in modern cars its all about the ecu . ive managed to pull my stock rom . and ive been checking out how to use the software , i feel comfortable using it i just like i said dont know what i should be tweeking and why
A good starting point might be to compare the timing map, fueling map, and OL/CL parameters between your base ROM and the ROM's available above. This will allow you to gain insight on one tuner's (SEAN-RIP) strategy. Again, every car is different, but this be helpful starting point provided you understand the ECU and it's knock control strategy.
Frankly there isn't alot of 'untapped free power' available without bolt on modifications and moving to a higher octane (89-91). Even with bolt ons and higher octane you don't have unlimited freedom in adding timing. You'll find knock sooner than later with pump gas. Understand the ECU and you'll find an answer to your 'why' questions
What are your mods and goals for the car? Are you willing to settle on a higher octane fuel? What is the fuel quality in your region?