Adding to the inventory of products to test out on the flow bench I’ve acquired a Silicone RS4 MAF accordion hose from 034 Motorsports. I didn’t pick this up just to test 034’s claim – “Features a larger inside diameter and smoother surface for better flow” but I will be able to put it to use on my car as well.
I made a couple of logs this afternoon to look into an apparent difference in the narrowband O2 sensor readings reported by ME7Logger and VCDS.
The VCDS data is B1S1 and B2S1 in the legend and also has fewer sample points on the chart. ME7Logger uses OSVoltageSensor1/2 in the legend. The wideband sensor is an Innovate LM-1 with tailpipe probe so the readings are post catalytic converter.
The VCDS logged event showed a slightly leaner AFR on the wideband which should have translated into some difference in the narrowband readings, the question is if the scale of difference in narrowband readings is appropriate for the different wideband measurements.
I also logged a slightly different boost profile as I work on trying to have an acceptable temporary tune on the car. This presented another opportunity to look into how the compressor absolute pressure relates to the manifold absolute pressure.
In hopes of getting some additional insight I looked at the pressure readings at idle. How much of this difference is due to pressure drop and how much to senor differences will have to wait for another event, next I’ll try logging both sensors with the engine off.
PSIa in the legend corresponds to the Turbo’s Compressor Absolute Pressure (CAP).
I’ve been playing around with a few canned tunes that I pulled from the Nefarious Motorsports site, this one I dropped the boost some but the timing looks like it needs a little work, that shift in timing can definitely be felt when pulling hard.
