RCPro AFR reading differs from Innovate Motorsports DB gauge
Posted: Fri Jul 19, 2013 2:05 am
Anyone running an Innovate Motorsports LC1 with the DB gauge?
http://www.innovatemotorsports.com/products/db.php
I've noticed that the AFR logged by the RCPro was reading about 0.5AFR higher than what was shown on the DB gauge. Strange, because both are driven by the same analog output from the LC1, according to this transfer curve.
Excel graph of what I was reading from the RCPro. Was about 0.5AFR higher than the gauge. I fed the voltage into another analog input and acquired that as the raw voltage to double check the scaling. No issues with the math conversion between voltage and physical units. I also tried to use the virtual gauge to compare against my multimeter reading, but that wasn't a good comparison method.
Took another look at how I had the other analog output of the LC1 programmed to fake out the narrow band signal to the engine ECU.
Hmm, my readings should be bouncing between 0.85lambda and 0.912lambda, which is 12.5 and 13.4AFR. Which pretty much agrees with what the RCPro was telling me.
So I think it's actually the Innovate Motorsports DB Gauge which is incorrect, since it reads lower than it should. I calculated that about a 0.2V delta would account for the differing readings. Maybe the ground for the DB Gauge has a slightly higher resistance so the voltage is a little lower, causing the lower AFR?
Anyone else experience this when comparing their RCPro readings against their Innovate gauge?
http://www.innovatemotorsports.com/products/db.php
I've noticed that the AFR logged by the RCPro was reading about 0.5AFR higher than what was shown on the DB gauge. Strange, because both are driven by the same analog output from the LC1, according to this transfer curve.
Excel graph of what I was reading from the RCPro. Was about 0.5AFR higher than the gauge. I fed the voltage into another analog input and acquired that as the raw voltage to double check the scaling. No issues with the math conversion between voltage and physical units. I also tried to use the virtual gauge to compare against my multimeter reading, but that wasn't a good comparison method.
Took another look at how I had the other analog output of the LC1 programmed to fake out the narrow band signal to the engine ECU.
Hmm, my readings should be bouncing between 0.85lambda and 0.912lambda, which is 12.5 and 13.4AFR. Which pretty much agrees with what the RCPro was telling me.
So I think it's actually the Innovate Motorsports DB Gauge which is incorrect, since it reads lower than it should. I calculated that about a 0.2V delta would account for the differing readings. Maybe the ground for the DB Gauge has a slightly higher resistance so the voltage is a little lower, causing the lower AFR?
Anyone else experience this when comparing their RCPro readings against their Innovate gauge?