Especially with long tube headers you're going to want to get your O2 Transport Delay dialed in before moving on to MAF or SD tuning. There is an ECU learned offset but the closer you get to the actual values the better, especially in out-of-idle conditions (1500-5000 RPM). Getting these values dialed in effectively increases the responsiveness of your O2 fueling correction. By adjusting the transport delay from when fuel is injected to when the O2 sensors apply a correction, you can more accurately match the physical time the fuel takes to get to the sensors. End result, you'll see your short term corrections happen much quicker when there is a difference between the WB EQ and the Cmd EQ. However, applying a baseline correction across the entire table can result in slower short term corrections, poorer fuel economy, etc.
General guidance would be to apply a baseline correction (+25%) across your idle columns (600, 1000, 1250 RPM) to account for the increased distance of the O2 Sensors, then data log O2 Transport delay using RPM & Airload as your column and row axis to determine the actual transport delay for the non-idle columns. You'll want to set your "Cell Hits Required" for the graph to 10 (or something similar) and increase the O2 Transport Delay Total channel polling interview to 20ms to ensure you're getting accurate data.
Go out and work through populating as many cells as you can. Its often helpful to switch between drive modes, put the car in sport mode and manually switch between gears, etc. Once you've filled most of the cells in your data log graph, you can use some simple math to calculate the new values for the non-idle columns (1500-5000 RPM) in the Transport Delay table. Since the data in the Transport Time Constant table represents the physical sensor response time, you can subtract the Transport Time Constant value from the logged O2 Transport Delay Total value for each cell to determine the correct Transport Delay table values.
Example for 1500 RPM @ 40% Airload:
Logged O2 Transport Delay Total value: 0.494
Transport Time Constant value: 0.260
0.494 - 0.260 =
0.234 (New Transport Delay value)
Here is a link to our instructions & calculator for making this process easy. Just click "Use Template" to create your own editable copy.
Sector Racing - O2 Transport Delay Calculator