Thanks flyingfinn. I'm working on the fixed Wideband in addition to the pulled-narrowband products. A fixed Wideband of course requires replacing the O2 sensor. The pulled-narrowband approach just means opening a connector and installing a circuit between the open ends. Different degrees of difficulty and different costs. If there was a Wideband sensor with fixed shift my tests and experience say that 4-6% shift in lambda to 0.96-0.94 would be about right. I'd be interested in whether people would want 4% which takes care of most of the driveability issues (and leaves the catalytic converter functioning a bit) or 6% for a bit more punch. Maybe a 0.5 mpg difference between the two.