Closed loop?

[KRatcliff]

There are multiple reasons why I wouldn't run closed loop. The ECU can calculate very quickly, but the information coming into the ECU isn't reliable nor can the ECU read the information and make the necessary change to improve the performance within the short time of the pass in my opinion.

Our passes are only a few seconds and they are even shorter when you consider the gear changes. The ECU would have to make these adjustments reading off a single O2 sensor that isn't exactly in a sealed environment and it is only reading on bank of cylinders for an average. Plus the O2 sensors don't exactly like the fuel that we run.

When you consider these factors the ECU would be behind the curve in reading the data, calculating the change, and then effecting said change. I tune our cars in Alpha N/Open Loop in 10 different sections (for a 3 speed). The 2 Step (this would be chaos for closed loop) and 3 sections for each gear for a total of 10.

My fuel map leads in at each section similar to how we all use timing advance. There is also a cumulative affect that needs to be considered. None of this is possible with closed loop in our applications in my opinion. If closed loop was an advantage down track the Pro Stockers would run it. Closed loop is best suited for street cars.