datalogging for PefTb tuning in MPTune
So I'm running a turbonator cal and have ordered a sci cable from Rob (should be arriving in the mail today)
I've read through the MPScan thread, and have some questions.
On the wiki page http://www.boostbutton.com/turbonato...-peftbl_tuning it states that you need "good" logged afr data.
would I have to send a wideband signal to the computer to be able to log accurate data? I have an LC-1 and am currently sending the computer the narrowband signal instead of the wideband.
Re: datalogging for PefTb tuning in MPTune
You don't have to send the AFR data to the ECU to log it. I've done the adjustment from data that came from a dyno datalogger (including an RPM tap and a separate MAP sensor).
By 'good' data, I meant that it really needs to be WOT only. So, if you are taking data on the street, you will need to do a lot of manual filtering.
Re: datalogging for PefTb tuning in MPTune
It needs to be wot and fairly steady state. Ultimately you want to slow the process down as much as possible so you get good solid repeatable data for each rpm point. Ride the brakes hard at WOT to accomplish this.
Ideally (think engine dyno cell) you want to load up the motor and hold it at a single rpm point at WOT for a little while till the temperature stabilizes before you take readings.
Riding the brakes hard while hammering the car at WOT will slow things down to get this pretty close to ideal.
Re: datalogging for PefTb tuning in MPTune
Ok first things first - get MPScan to recognize the sci cable
I'm running Win 8.1 x64, plugged in the cable and it auto-detected and installed the device drivers. I updated to the newest drivers from the ftdi website, downloaded ft_prog and programed the device based on this guide
http://www.turbo-mopar.com/forums/sh...-datalog-guide
MPScan still says No Valid Ports
everything looks good under Device Manager, but I don't have the port settings tab under the device properties.
Re: datalogging for PefTb tuning in MPTune
Quote:
Originally Posted by
streetpirate
Ok first things first - get MPScan to recognize the sci cable
I'm running Win 8.1 x64, plugged in the cable and it auto-detected and installed the device drivers. I updated to the newest drivers from the ftdi website, downloaded ft_prog and programed the device based on this guide
http://www.turbo-mopar.com/forums/sh...-datalog-guide
MPScan still says No Valid Ports
everything looks good under Device Manager, but I don't have the port settings tab under the device properties.
Unplug and replug the cable?
Re: datalogging for PefTb tuning in MPTune
Ive restarted the computer, plugged in and unplugged the cable, tried plugging in the cable with mpscan open as well as opening it after the cable is pluged in and recognized by windows.
Is there any setup that needs to happen in mpscan BEFORE I try to plug the cable in? Does the ignition have to be on for mpscan to detect the ftdi cable? (I have tried both ways but good to know how it's supposed to be)
Re: datalogging for PefTb tuning in MPTune
Figured it out
in ft_prog under hardware specific there is an option that came pre-ckecked to force it to only load the D2XX drivers and disallow the virtual com port drivers to load. unchecked that and reprogrammed and it works!
Re: datalogging for PefTb tuning in MPTune
Hmm, that shouldn't work. Or, I should say, usually doesn't work...
Re: datalogging for PefTb tuning in MPTune
So now that I have MPScan working what is the best way to log afr data for PerfTbl tuning?
It seems the best way would be through the ecu so the data points all line up between map, rpm, and afr. I have an LC-1 with the serial output (which i have never played with).
So what's the best way to do it? Send the WB to the O2 input of the ecu? Unhook the Charge Temp sensor and send WB data to that ecu pin to log? Somehow get MPScan to talk to the LC-1 and the ecu at the same time?
Re: datalogging for PefTb tuning in MPTune
Quote:
Originally Posted by
streetpirate
So now that I have MPScan working what is the best way to log afr data for PerfTbl tuning?
It seems the best way would be through the ecu so the data points all line up between map, rpm, and afr. I have an LC-1 with the serial output (which i have never played with).
So what's the best way to do it? Send the WB to the O2 input of the ecu? Unhook the Charge Temp sensor and send WB data to that ecu pin to log? Somehow get MPScan to talk to the LC-1 and the ecu at the same time?
I had the same LC-1 and I did the AFR logging and then synchronized them. Its an unpleasant process and I am a ninja in excel. There are two problems:
1) is that MPSCAN and logworks do not sample their respective things at the same sampling rate
and
2) its somewhat ambiguous exactly where logworks starts logging..the start time is only precise to 1 second so I just assumed it meant 1.000 seconds..but that is a total guess and could easily be wrong. This can mess up your AFR to MPSCAN relationship to the point where its useless. Or at least, for what I was doing it was. 1 second is a long time.
So, what I had to do to "synchronize" them, was to create a new dataset that had interpolated values from the slower dataset at the same timestamps as the faster dataset (i forget if that was logworks or mpscan). Then I could line them up. But the start point was still ambiguous and I dont think its correct to assume 1.000..the data looked off. The interpolating process is annoying but doable.
Re: datalogging for PefTb tuning in MPTune
Quick question: What size sample would be considered desirable for this?
Seconds of data? Minutes?
You want all constants as close as similar, so would taking samples from separate runs be bad?
Re: datalogging for PefTb tuning in MPTune
Quote:
Originally Posted by
krut
Quick question: What size sample would be considered desirable for this?
Seconds of data? Minutes?
You want all constants as close as similar, so would taking samples from separate runs be bad?
I dont think averaging multiple runs is required. You will be doing multiple runs to incrementally approach the right tune anyways. You dont really have control over the sample length because the engine state is changing unless you are on a dyno that is literally maintaining a static rpm. Your main problem will be creating a representative load using just the brakes, but others seem to have luck with that so maybe it works
Re: datalogging for PefTb tuning in MPTune
I have done this using my own drag race data; and for a customer using dyno data. I can tell you, the dyno data is the best way. My drag race data was so limited, that I was only able to really tune the PEFTBL from 3k to 5k rpm. Which I guess is fine for the limited use of my car (drag racing). But, for general tuning, a chassis dyno would be the best way to get data over a wide RPM range.
The brake trick will probably work OK; but I would do it at low or no boost.
Re: datalogging for PefTb tuning in MPTune
the brake trick is hard for automatics because of the stall of the torque converter. you can only load the engine hard at WOT above the stall speed.
so if you have a higher stall converter, what are you going to do? put in a low stall and tune and then swap out? most wont do that.
or swap in a manual tranny, put a vac pump on the brakes to make sure they work and drive around hammering against the brakes to tune the below stall speed rpm fuel and then put in the auto?
or tune at the stall speed and then set FuelBaselineFromMap to 14.7 afr (or whatever you want to idle at) at the vacuum level you idle at and then tune idle RPM pumping efficiency with o2 feedback turned off and then blend the pumping efficiency from idle to stall speed?
or set part throttle, and no throttle and full throttle to the same afr curve in vac and low boost and disable o2 feedback and then tune the RPM points up to stall speed in part throttle?
im guessing getting idle good and solid with no o2 feedback and then stall speed good at WOT and then blending the curve is probably the easiest and will get most folks there....
if i was on the dyno, id ride the brakes on the dyno to keep the engine at a steady state RPM if its a dynojet or other inertia to make sure that point is exact. running up the dyno fast is still too fast alot of the time. ive seen cars come off the dyno running perfectly and as soon as they hit street loading in high gear, they ran like crap cause the load was different.
Brian
Re: datalogging for PefTb tuning in MPTune
EDIT: Brain fart. If I can get my laptop to talk nice to the LC-1 I can just program both the analog outputs to be wideband and turn on wb2nb in the cal. That takes care of the logging issues (theoretically)
So to take this back a few steps as to why I really want to do the perftable tuning...
I'm running too rich under boost. By 3psi my afr drops to 10.8 and higher stays steady at around 9.8. It does this in part and full throttle. Cruise does the normal (I guess?) hunt/bounce between about 13.8 and 14.7.
I'm beginning to wonder if the tune is fine and there is something else going on. Maybe my +40 injectors are really more like +45 or +50, maybe the scaling is off since I'm using a gm 3-bar map instead of a s60 3-bar, or the stock fpr is not working correctly.
I'm going to start with buying a harbor freight fuel pressure gauge and checking pressure under boost. I've read that the scaling difference between the maps is very small so I dont know if I should mess with it, maybe someone will chime in?
If the fuel pressure is rising correctly then I was thinking about changing the injector scale up a bit and retesting.
Looking at the perftbl between the stage 4 cal (or stage 3) and stock there is very little difference. Thats why I'm thinking there is another reason why my actual afr seems way richer than the fuelpartthrottle or fuelfullthrottle scale.
Re: datalogging for PefTb tuning in MPTune
Have you tried taking some fuel out? I *THINK* I may have ran into this with my setup, but it's been so long that I've driven my car that I can't remember what I did. Do the fuel tables have boost on the Y axis?
Re: datalogging for PefTb tuning in MPTune
I have not changed the fuel tables at all yet. They are injector pw on the Y and map on the X. I'm just concerned that my actual afr is so much different than the calculated afr in the fuel tables.
Also, what is the function of the fuelbaselinefrommap? I don't see it mentioned in the descriptions of fueling calculations? http://www.boostbutton.com/turbonato...?id=fuel_setup
- - - Updated - - -
btw,
'89 intercooled garret 2.5, gm 3 bar map, +40's, 3" swingvalve and exhaust, t1 boost control, running turbonator stage 4 cal
Re: datalogging for PefTb tuning in MPTune
Quote:
Originally Posted by
streetpirate
I have not changed the fuel tables at all yet. They are injector pw on the Y and map on the X. I'm just concerned that my actual afr is so much different than the calculated afr in the fuel tables.
Also, what is the function of the fuelbaselinefrommap? I don't see it mentioned in the descriptions of fueling calculations?
http://www.boostbutton.com/turbonato...?id=fuel_setup
- - - Updated - - -
btw,
'89 intercooled garret 2.5, gm 3 bar map, +40's, 3" swingvalve and exhaust, t1 boost control, running turbonator stage 4 cal
The stage 4 cal has modifications to the PEFTBL that assumes you have a mildly ported head. So, if you don't, it will run richer.
Maybe start by comparing to a stock cal, and resetting the PEFTBL to stock.
Re: datalogging for PefTb tuning in MPTune
Rob, I have been running the stg4 mainly because it was already set up for +40's, but I did try the stage 3 cal for a day scaled for +40's (only change) and I was seeing a similar rich condition.
the PERFTBL on the stg3 is identical to the stock cal (looking at the '89 2.5 atx a135)
So running a stock 782 head and one piece intake I guess I should really be using the stg3 cal as a starting point.
a question on boost control:
I wanted to set up an 8psi limit on the cal so when I start playing with fueling I'm not running high boost.
I set the allowedboost from speed, temp, and tps volts all to 7.5 max and I'm still getting 18-19. I don't know if it's related but every time I disconnect the battery I get some overboost to 20psi the first couple days (hits cutout) but it has always mellowed out back down to 18 and never hits overboost again. I don't really understand how the wastegate adaptives work but they seem to work fine after the 2nd or 3rd time it overboosts.
Re: datalogging for PefTb tuning in MPTune
I'm running +40s and scaling for 58# injectors got me the closest starting point. Still had to take some fuel out WOT and had to add it in low vacuum areas.
What engine are you running, 2.2 or 2.5?