Ve table tuning opinion
Well from what I've read here I'm going to disable ltft and tune the ve table with afr error histogram. Seems to be the quickest way to get going. Whats a good cell count the start with? I just checked and mine was previously at 5 so I'm sure most my logs were trash.
Depending on how aggressive the cam profile is I like to go with 15-20 Cell counts on Lambda Error.
As for your earlier question,
LTFT's are derived from the AVERAGE of the STFT's... IE- STFT are bouncing between 2.0 - 6.0 during MAF HZ of 3500-4300 at 1200rpm - 2000 rpm... MAP KpA of 30-40.
The LTFT's would try to keep the STFT's as close to 0 as possible (THEY WILL NEVER REACH ZERO!!!). So the LTFT's in the example above would tend to lean towards 4.0.
Now, understanding Cam profile comes to play when calibrating..
If you are using a very aggressive cam shaft (Say 254/260 .631 .611 109+2 LSA in a 370cu in LS2). You would need to tune the car in Open Loop.. The overlap of the cam shaft will blast the narrow band o2 sensors with false readings. Bouncing the STFT's from +15 to -10% rapidly at best.
Infact some of the standalone units recommend tuning Closed loop correction off for very aggressive cam profiles with Wideband o2 sensors controlling the ECU.
In final, what does you combo look like and what are the intended driving habits?
As for your earlier question,
LTFT's are derived from the AVERAGE of the STFT's... IE- STFT are bouncing between 2.0 - 6.0 during MAF HZ of 3500-4300 at 1200rpm - 2000 rpm... MAP KpA of 30-40.
The LTFT's would try to keep the STFT's as close to 0 as possible (THEY WILL NEVER REACH ZERO!!!). So the LTFT's in the example above would tend to lean towards 4.0.
Now, understanding Cam profile comes to play when calibrating..
If you are using a very aggressive cam shaft (Say 254/260 .631 .611 109+2 LSA in a 370cu in LS2). You would need to tune the car in Open Loop.. The overlap of the cam shaft will blast the narrow band o2 sensors with false readings. Bouncing the STFT's from +15 to -10% rapidly at best.
Infact some of the standalone units recommend tuning Closed loop correction off for very aggressive cam profiles with Wideband o2 sensors controlling the ECU.
In final, what does you combo look like and what are the intended driving habits?
My combo is mainly stock.
I have a Vic jr intake, arrons elbow, 92mm tb, and nitrous that's it.
Driving habits are hold the trans brake, floor the car, and let go when I see a flash of yellow lol. The more I'm reading it seems a SDOL tune would suffice for my cars purpose.
I have a Vic jr intake, arrons elbow, 92mm tb, and nitrous that's it.
Driving habits are hold the trans brake, floor the car, and let go when I see a flash of yellow lol. The more I'm reading it seems a SDOL tune would suffice for my cars purpose.
