[Joe Schmoe]

My PPE header came with two bungs after the collector. I split the signal wires from the front O2 sensor to both signal wire inputs. I then installed the 2nd O2 sensor in the rear bung and used only it's heater wires...mostly because I didn't have an O2 bung plug. Everything soldered. The car runs very rich this way. Unless I'm mistaken it's because the O2 sensor is now much farther downstream than stock. If you have the means, I'd recommend trying to have the two O2 bungs welded into runners 1 and 2 at the proper distance from the head as Cap described as one of the options. I think this may result in a better mixture.