D1ck3y0da
New Member
Guess ill keep searching. Thanks.
What is it that you are trying to accomplish? I think I've mentioned this before, there are fuel trims embedded in the ECU software.
Here is a cut-n-paste I found from another thread origionally posted by member krid80:
I believe our resident expert is Scott (aka @TownsendsFJR1300). Perhaps he can chime in and give you (or link you to) the full story.
So adding inlet air pressure to my pcv w/auto tuner will better allow it to make a better map? I've noticed my auto tuner likes to add crazy amounts of fuel (spmetimes +50%) very low in rpm (2500k-7000ishk) @2%- 10% throttle and you can feel it when it hits a crazy high number. I normally have to go into map and adjust. My next question is if I can add pressure sensor how do I calibrate it? Any information will be appreciated. Thanks.
Yes mate the auto tuner has a wideband and a table that tells the pc5 ok i want this afr for this rpm with this throttle. Ex 2%throttle at 4k rpm, 100% at 10k rpm, so on an so forth. The auto tuner don't always want to add 50% fuel at 4k rpm with 2% throttle but it has and I know that much fuel that low is very costly! As I stated im try to get better drive ability out of the autotuner and provide it with as much information as possible to better pick which value of fuel %.Before you embark on a tune, you NEED to ensure that the fueling system is in tip top shape. For example, you state the the autotuner is adding 50% more fuel. That is not correct. It is increasing the duty cycle of the injectors by 50%. Without knowing the resultant AFR the duty cycle is meaningless. If the injectors are not delivering normal amounts of fuel, then the autotuner is trying to get things back to normal. And one thing for sure, if you start advancing timing on a motor that has fuel delivery problems, you will make LOTS of power.... in the few moments the engine has before it grenades!.
A lean mixture on a stock motor is survivable, because Yamaha builds in lots of safety margins. Start squeezing those margins and you are flirting with disaster. Take it from someone who has been tuning Subaru engines for years.
Don't know your experience. If you have done this before, you know all this, and that's great. If not, be careful and make small moves. A 12.2 compression ratio on pump gas can make the intake charge VERY energetic. Without a wideband O2 sensor, a knock sensor and really good logging (throttle position, AFR, advance, knock events, etc) you can get into irreparable trouble in the blink of an eye.
Good luck and keep us informed. We can all learn new things.