Well, welded the bung into a friend's test pipe 3" in front of the cat flange and did about an hour's worth of tuning tonight. Okay, did about 10 seconds worth of tuning and 59:50 worth of playing
. It's neat. Right now we only have the O2, no rpm or tps input. Hit the record button, started ds logging, and then did launches to see why we have a stumble. It was pretty easy to tell in the wb log when we hit it because there was a blip upwards in afr from 14 or so up to 16, for about a second, then down to way rich 9.5. His narrowband O2 is dying from lead and I was trying to bandaid the stumble with more pe fuel instead of going into the ae tables - these are Delphi injectors and the only big injectors I've tuned so far are Siemans and these are way different on the bottom end. I could see the lean tip in on ds but the o2 has lost so much range that the O2's only got up to about 750 mV when the wb said 9.5! I knew I was too rich but went with the O2's at first just to see where they would lead. This stuff is fun!
I did have a lot of trouble getting a connection to the serial port to upload the data to my laptop. I'm running w95 on an old ibm thinkpad 760xl, and many times the software would say "connect device and turn on", then hang forever. I'm still not sure what magic incantation let it work. Oh, it can record for what, 44 minutes (?) at 12 frames per second, and you can just hit the record button to stop and start recording as many times as you want. When you upload the data, each recording event is a separate "session" so you don't have just one long record to scan through and guess when you stopped and started. I'm not sure w95 is really supported or not - I may need to install the w98se I have laying around after upgrading my desktop to xp pro since ds will still work okay with that.
I'm going to ask Santa for the rpm input cable and put a bung on my car Real Soon Now (tm) (for you old Jerry Pournelle fans
). It is real awkward sitting in the passenger seat with y-socket in the cigarette lighter, inverter on floor, laptop on lap plugged into that and parallel port a/b switch to the ds cable, lm1 plugged into y-socket and serial port on pc and cable out window to sensor sitting on the console or lap, pocket programmer plugged into inverter and a/b switch, and ecm on floor with ds cable and cable to remote chip box with flash ram chip on the console next to the lm1. After I sat down it took a good two minutes to plug everything in, with the driver handing me each piece to add to the pile
. There's got to be a better way.
No heat sink on sensor but we are way downstream of turbo and only made three wot passes to about 75 mph. No problems with sensor overheating.
About all you can do in the software is drag a slider through the data while looking at the afr number and time in a box below the graph. With more inputs there would be more lines, which is good but can be confusing. I would like the option of separate graphs like the scope display in ds. Also, it would be nice to use the left and right arrows to step through the data instead of having to drag the slider.
It's not clear from the manual if the o2 sensor is kept heated while the lm1 is in serial mode. We kept the engine idling for a few minutes to keep the heat on, and then realized that we might be hurting the sensor since it will quickly foul if you run the engine with the sensor cold. Didn't seem to hurt it but gave me a scare, sigh.
Well, those are my first impressions. After some more use I'm sure I'll get the connect problem licked and I'll post some more observations.