Anyone worked with the 16196397 yet?

[RobertISaar]

i don't think you could log data fast enough with anywhere near a full stream to get reliable cylinder-by-cylinder results(at 2000 RPM, if you're running a single O2 sensor and having all cylinders passing exhaust to it, that's (((2000/2)X6)/60)=100 exhaust pulses per second).... you can get a solid 700 bytes in/out of the PCM per second including overhead, but you would need a pretty short stream(perhaps with less a comm scheme with less overhead) to get raw AFR values and a cylinder identifier for each value.

alternatively.... you could have the PCM do a lot of math on its side of the fence and have a rolling average of the AFR seen for each cylinder. then send the AFR for each cylinder as a separate byte in a stream. seems like it would take considerable amounts of RAM to have a decent average... 6 cylinders, 10 sample history and a final, averaged value to send to the laptop is 66 bytes.... I don't know how far the stack will run down on the E-side(I don't know if I've ever monitored it), but it has from 369-5FF to work with in a factory calibration.... there is probably more than a sufficient amount to go about this kind of scheme. the problem I forsee is trying to correctly separate the exhaust pulses in the O2 sensor logic. I don't remember if that is run at a 80 or 160Hz rate, but 80 would allow for 4,800 samples to be taken in a minute... divided between 6 cylinders, that's only 800RPM before pulses get mixed/missed. 160 only brings it up to 1600. 160 and only monitoring half of the cylinders brings it up to 3200RPM.

for the weight of your truck... I think I would start with a L/N calibration rather than a W. after all of the rework you're going to end up with doing in the calibration, it probably won't matter that much though.

[Xnke]

Truck weighs 2990lbs with a full tank and no one sitting in it. Just weighed it today, actually.

I know that my Innovate LC1 wideband easily discerns cylinder-by-cylinder when I use it with Megasqurt, for instance I know that Cylinder 1 in my datto runs a little too rich compared to 2, 3 and 6, but 5 runs right alongside it.

I'll start posting screenshots of the calibration as I make changes, just to make sure I don't do something stupid and assume that it's correct.

[Xnke]

Holy shit, no wonder these engines had cooling system problems. Fan1 turnon at 225F, fan 2 kicks on a 304F??? This is the 1994 L-Body bin, by the way

I managed to change the Injector Flowrate to 36lbs/hr, fixed the Low-BPW table (good grief that's a lot of cells) and the Injector Pulsewidth Adder-vs-Fuel Pump Voltage, I multiplied the 3.1L fuel table by 1.1, and I copied the 100kPa column of the Main VE table to the 100kPa column of the Boost Main VE table.

I set the following:
Use Vaccum or MAP for Open Loop AFR (X For MAP) Set
Use Vacuum or MAP for Open Loop Closed Throttle AFR (X for MAP) Set
2/3BAR Map Support (X for MAP) Set
Max MAP for Highway Fuel/Spark is set at 90kPa
Map Sensor A/D Offset to Represent 100kPa is set at 117
Map Sensor Scalar to Make Normalized MAP For Boost Calcs is set to 1.0000
1BAR emulation - 10.3kPa A/D Offset is set to 2
1BAR Emulation - A/D Count Multiplier is set to 2.117 - Autochanges to 2.109?

That's it so far for tonight.

[RobertISaar]

the O2 logic could be changed around to monitor individual cylinders at nearly any speed and cylinder count, but the fixed frequency method of doing O2 updates would have to be replaced with variable frequency code.... essentially tying it in with reference pulse interrupts.

that fan1 setting is common, but the reason you see 304 for fan2 is because l-cars never had a fan2. as a rule, I set my fan1 ~10*F above my thermostat temp and I'm pretty happy with it. depending on ambient temps, I actually can't get the 95 3100 monte carlo to overheat, even after idling for 45 minutes(at ~55*F), the coolant temp never reaches 205*F. idle advance appears to have a considerable impact on the amount of heat making its way into the cooling system.

for the value changing, that's just the limit of 8-bit math. with a range of 0-4 with 256 possible values, there is a resolution of .015625 per bit.

the vacuum/MAP bits probably won't have a huge effect for you unless you live at or travel through some significant elevation change, but it does make things simpler to look at. for what it's worth, I have the tables setup as if they're being viewed for MAP already.

[Xnke]

Eh, the O2 was just thinking out loud-I don't need/want to really deal with that level of precision on this engine.

Getting down to the list of stuff I do need to figure out yet:

I need to figure out how to control the EGR outputs-I need to toggle EGR #1 based on throttle position, and nothing else. (gonna use it for the boost control solenoid) I'd like to use EGR #2 to toggle the intercooler pump, but I don't see a way to seperate control of that output from the EGR system and tie it to the A/C Evaporator temp input. On that note, I need to disable references to the evaporator temp, since I don't want the intercooler temperature to mess with the A/C system!

I am going to use both fan outputs to control the 16" two-speed electric fan, using the existing fan logic. Nothing huge changes there.

I am going to lift Pin 60 on the E-side MCU and tie it in to A28 as a 0-5V wideband input, hoping to log Wideband-vs-Rpm-vs-MAP. Ideally the wideband would read out directly as AFR or lambda, as that would make tuning quite a bit faster. Having it log as a table vs RPM and MAP would mean being able to use Excel to compare the wideband output vs commanded fuel, similar to the way that BLM history is already used. Maybe actually using the same Tunerpro methods for recording BLM would work and there would be no need for a table in the PCM? Do all the table-izing in Tunerpro?

[RobertISaar]

what kind of impedance does the boost control solenoid and IC pump present? using the EGR1 output, you're going to be limited to about .75 amps(I think). I'm sure I've pushed the quad drivers further than that, but that is about where GM starts doubling up quad driver channels for more current capacity. EGR2 is the same .75, EGR3 is a doubled circuit, so ~1.5. with the IC pump, you're probably going to be using a relay, so maybe .2 amps will be seen by the quad driver to keep the relay controlled. if you wanted to play with some PWM-controlled coolant pump stuff, a solid-state relay or some creative use of a transistor or two would get the job done.

controlling EGR based on TPS alone isn't going to be difficult, that's a pretty small patch to accomplish. for that matter, controlling an IC pump based on the former evap temp sensor circuit is simple too since everything is on the E-side. another small patch and it's good to go.

with a non F-body BIN, any kind of signal on the a/c temp sensor circuit isn't going to upset anything since only the f-bodies used that function. even then, I'm sure there is only one flag necessary to turn off that function.

wideband can be made to read however you want... normally, the raw a/d value is going to be output over the datastream for tunerpro to do conversions on to meet the user's requirements. running its data into a table may have a few issues, namely if the target AFR for a given cell changes for any reason. then the history data is going to be skewed. perhaps a new value and table in tunerpro, one that represents a ratio of commanded AFR to read AFR, then that could be output to a RPM vs MAP table.

[Xnke]

Boost control solenoid isn't much, maybe half an amp at most. Intercooler pump draws 10-15amps, so it will be on a relay. I took your advice and am starting with a 94 L-body bin.