Turbo 2.8 tuning with logs and tune(need help with tuning)

[WillExoIX]

Im going to be posting my logs here as well as the thirdgen.org forum for feedback.

This is the first time I actually was able to take it out for a log after working out a leaking oil return and a pcv valve not sealing completely under boost. Still have a valve cover gasket leaking but its not a serious leak.

This is a log of me taking it out to the gas station a couple miles down the road. Megatune locked up when I started the car for the drive back, the area with the time gap was when I was getting gas. There are some glitches in the log, Which has been narrowed down to the usb cable to the laptop, the car does not glitch or hiccup at all. car runs flawless except for needing to be tuned.

If you dont remember my other thread with info on the car and hardware I will post it below.

1989 Camaro RS 2.8L V6
Mercedes 300SD Diesel T3 turbo (3L)
9PSI wastegate spring
Top mount intercooler
Megasquirt 1 running MSextra
280,000 Miles without the turbo

GOALS-NOT power. Going for the midpoint between power and efficiency. Was able to get approx. 33MPG NA. This is and will stay a daily driver.

Let me know if you would like to know anything else about the setup.

I will post the tune up shortly

[WillExoIX]

Here is the tune.

Further information;
8.5:1 CR, flat top pistons, stock iron heads, 36lb bosch 3 injectors, more or less completely stock motor.
60* V6 motor running 9.5PSI. 160* thermostat, fan controller set for 170*. Colder than stock plugs regapped from .045 to .025 for boost.

Im needing help on spark timing, no access to a dyno, only able to tune by "seat of the pants" on the road.
Mostly 32* max timing as a safe value, lower under boost and all in by around 4000rpm. Boost starts building around 24-2500rpms, and seems to be all in by around 3000rpms.

Its sluggish up top, though the VE still needs tuning. Im working on scaling the table back by .98-.99 increments at a time, and correcting where it goes too lean for now. Seems to run around 11-11.5 or so AFR under boost, but I try not to take my eyes off the road. Its an empty road close to my house, about a 2 mile straight stretch.

Also have no knock sensing as of yet. Currently no funds to invest in a GM knock sensor, and I am only missing the LM IC for the knock sensing circuit. Also would like to work on manifold air temp correction when things are mostly dialed in.

[Matt Cramer]

Unfortunately, a data log won't help much with spark table tuning. This article has a few tips, but this is a big challenge to really get dialed in without a dyno.

http://www.diyautotune.com/tech_article ... rt_ems.htm

[WillExoIX]

Thanks Matt, though I have already looked over that article a few times. I have a couple people running the same engine setup that I can base my table off of on the thirdgen forums.

One thing I think I would like to get some feedback on is how the log looks. I know what Im looking at, but unsure of how to read into whats going on with the engine. Like the MAP values, would I be able to tell if say a valve isnt completely closing by how the MAP value acts throughout the log?

It pulls hard when the boost starts building, but starts to get sluggish at mid-range rpms. I know it can pull harder than it does, hence the need for tuning. Though I suppose it could also be the trans slipping a bit. Either way its a little sluggish, and im thinking possibly a misfire or valve not closing completely, but need to pull the plugs and do a compression test.

Any tips on reading more into the logs?

EDIT-Added to post below

It idles kinda like its missing, rough, motor rocks a little bit. more than before, but I know the turbo is a restriction at idle. I dont know, just doesnt seem like its running right for me to be comfortable enough with it to take it out tuning.

Most of the time, 1/8th on the throttle now drives like 3/4 on the throttle when it was NA, but it seems to fall off quick around 4500 or so rpms. But up there its also going to the high 10s on the AFR. I know too rich will be sluggish, plus the timing still needs tuning.

It feels like misfire but I really cant justify calling it that because it drives well, but I cant really read all that far into the datalogs yet. I know what im looking at, guess Im just having trouble linking everything together to read how its actually doing. I know TPS, MAP, RPM, AFR, etc... low MAP=high vacuum and vice versa, RPM is obvious as well as TPS and AFR. But the small spikes and other things in the MAP plot, what does it mean?

I know high duty cycle is running out of injector/possibly fuel pump, pulse width is the pulse of injector, like I said I understand that all but what am I actually looking at? Its kind of hard for me to put into words what Im trying to convey here, just hoping you get what Im trying to say.

[WillExoIX]

Guess I need to be more specific to get a response.

I know what the log shows, How do I determine what the log is telling me about the engine?

How do I tell if its happy or running like crap?

I understand the parameters, but how do I know that the engine likes what I'm doing instead of the "butt dyno" method?

[Matt Cramer]

I've been thinking of putting together a tutorial on data log reading, but here are some of the short versions of things to check for.

1. Temperature sensors should move slowly and read ambient temperature on a cold start.
2. MAP sensor should read typical ambient pressure with the key on and engine off, and more or less tracks with the throttle (at least off boost).
3. Injector duty cycle shouldn't be over 85%.
4. AFR readings should be hitting your AFR targets.
5. RPM shouldn't be losing sync and dropping to zero or one, or suddenly being cut in half, etc.

[ihateforums]

I noticed a few things. 1) Your spark table looks pretty conservative. 2) Every once in a while in your log there is a row of completely insane numbers so you might be suffering from serial data corruption or power spikes. 3) Looks like you were running with EGO correction off?

[WillExoIX]

I noticed a few things. 1) Your spark table looks pretty conservative. 2) Every once in a while in your log there is a row of completely insane numbers so you might be suffering from serial data corruption or power spikes. 3) Looks like you were running with EGO correction off?

1) Yes its a bit conservative. I have been working on a new table as a better starting point from someone running the same motor with a turbo. Still staying a little more conservative then his final SA table due to not having a knock sensor.

2) Its the usb cable, I'm going to eliminate the usb cable and go back to the serial cable, only using the serial to usb adapter at the end.

3) Yes EGO correction is off while I learn the ropes.

[WillExoIX]

Here is the new spark table I am running. This is my new starting point, and once I take it out and see how it does, I figure I will start scaling down the VE table little by little.

[WillExoIX]

Though I do have another question, not sure if you can see it in the original datalog or not.

When I first start the car, I have to give it a little pedal, because it drifts lean after startup. If I don't give it any pedal, it goes lean and stalls.

Would that be after start enrichment, Warm up enrichment, or which setting do I have to mess with to alleviate the lean swing on startup? This would be startup when cold.

I have the same issue on hot startup, but I know that issue will rely on the IAT/CLT compensation table

Edit- I am using Megatune.

[WillExoIX]

Cmon guys, need help ironing out the details. Or should this be put in the tuning section?

[Matt Cramer]

It may be time to switch to TunerStudio, but afterstart enrichment is active in the first few seconds after starting, and warmup enrichment is active until the engine comes up to operating temperature.

[WillExoIX]

Where is the config file for tuner studio to change some of the parameters that I keep getting errors on? One that is especially confusing is its telling me that my old tune file is set for PSI, when its set for Kpa?

[Matt Cramer]

That one sounds like it would be set in Project Properties.

[WillExoIX]

ok, thanks. Loaded it up in TS and no errors. Next question.

Hot start. Is that going to be the coolant related air density settings?

Example, lean when starting when heat soaked.

[Matt Cramer]

That can help. Relocating the IAT can as well.

[WillExoIX]

That can help. Relocating the IAT can as well.

The IAT sensor is about 6-12 inches before the throttle blade, The heatsoak would be even worse if it was inside the plenum behind the throttle blade. the AFR starts to vary as it idles while the IAT heats up, thats where the correction table would come into play correct?

[Matt Cramer]

Ok, I thought it might be in the plenum. Can you post a data log of the issue and a copy of your current MSQ?

[WillExoIX]

Ok, I thought it might be in the plenum. Can you post a data log of the issue and a copy of your current MSQ?

Will do. I will do that first thing tomorrow.

I will start it and let it stall without giving it any gas so you can see that issue. Then I will let it warm up and heatsoak while running so you can see the AFR wander. After its warm, I will shut it down, let it heatsoak, then do a hot start and see if it stalls like it normally will. Then I will post up the log, and the MSQ.

Thanks for the help Matt.

[WillExoIX]

Here is a log and current MSQ. I know the TPS is reading 26, I forgot to recalibrate it when switching to tunerstudio. Curiously it wouldn't start at all after I let it heatsoak, you will see how long I tried to crank it. Time gaps and the 1 reset was from me turning the ignition off. It goes to .9 degrees timing for cranking, That cant be right can it?

The log ends when the battery on the laptop started dying, 5 minutes later after I brought it inside, I went back out and the car started after a couple more cranks. was running 15.5+ on the AFR I am assuming because it was heatsoaked.

Beginning of the log is a cold start. It almost stalled but didnt, which surprised me. Usually I have to tap the pedal to keep it running. After that I let it idle till it was warm, then revved it a couple times so you could see what the AE is like currently. After that I shut it off to let it heatsoak, then it didn't start at all.