[beatr911]

I have to admit, a generic O2 sensor and an inexpensive gauge while appealing to my cheap side will unlikely be as accurate as a more expensive wideband kit.

For my setup I have noticed that for my best flowing pipe the engine acted as if it was lean and the gauge showed it slightly lean. For the pipe I have on now it runs perfect and the gauge shows a little rich. This corroborates what I've read that ICEs can run well farther into the rich zone from stoich than into the lean zone.

I look forward to reading your results whatever you end up with. Sometimes some instrumentation is better than none, provided you can accurately interpret what information is provided by it.