don't know how it works with a tweecer,but I have lm-1 kit and you weld in bung in the exhaust and hook that up to the meter and then you can read your a/f ratios. If you're going to do it you might as well get the lm-1 kit with the rpm adapter so you can do the data logging and read your rpm's too along with the a/f ratio. I have the pms and together they work great.