it's calibrated, div, what I was referring to is the idea to get better resolution. with 0-2V analog output, the minor 0.1-0.3V fluctuations makes the AFR readout a little wide. Most sensors are 5v, so the ecu can actually manage a 5v D14 sensor input. with 5v emulation on the LM1, the readouts are a bit more stable, since the LM1 analog output actually samples at 16 samples per sec, I tried lowering it to 1/6, but those minor fluctuations were still irritating when reading the map trace, so I tried 5v emulation and it works great.
there's a lot to play with div, if you're going to diy. Even without a dyno, you can aim for good AFR and with the LM-1 auxbox acceleration sensor, you can tune the ignition somewhat. But it's hard to tune a fast car because of the speeds involved in accelerating full throttle in 4th gear to peak rpm. we're talking 190kmh + on the streets and with a starting rpm of 2.5K, it's a LOOONG stretch of road, and retaining it for at least 10 secs or less to wait for the AFR to stabilize (the afr readout needs time to stabilize after hard acceleration due to the throttle tip in fuelling involved) I'm getting by with running slightly rich and lower timings at columns 9-10 at 7-9K (not that rich and retarded though), abt. 13AFR and 28's ignition. It's for a temporary measure though, as the exhaust is enlarged slightly recently to 2.25inches, so that's something. Haven't gotten the time to see how far up the peak power can be carried with a bigger exhaust, so that's something to be done a bit later. I still think it's better with a 2.5, but since it is an experiment, might as well see what can be done with a 2.25inch exhaust, and how far up the peak is.
With a slower car, speed's not an issue because the 3rd gear gives abt 140kmh max, and it's no problem to retain it that long if there's an empty street long enough, like abt 1km+
The reason why i'd use 4th gear for a dyno run is for the resolution. any misfirings or lean spikes can be seen with a 4th gear run that might be missed when doing a 3rd gear run that lasts 3-4 secs or less.