View Full Version : tuning GM TBI system WOT

03-20-2011, 06:29 PM
I am running a GM tbi on my International Scout II with a 345. I have a small cam in it.
I have a 7747 ECM and I am running a 350 tbi. I also have a WB O2 sensor.
I am using a Moates APU1 for programing and emulation. Tuner pro 5 4F definition

I pretty much have all my cells in the 128 range, give or take a few points either way. 126-130.
What do I need sorted out, before I can start tuning WOT? and how do I go about tuning it?
I know there is a table VE2.

03-21-2011, 01:24 PM
Sounds like you should have been tuning WOT already. :P

With idle and low RPM tuning close, you can ease into WOT. Keep an eye on things, like AFR, engine temp, knock, etc, etc, and just add or remove fuel and spark as needed. You may want to go a few hundred RPM at a time, if you feel the current bin would be pretty far out.

A different train of thought I've read about people using is to tune idle an part throttle drivability, then go straight to tuning WOT, at which point they can extrapolate the tables in between.

Personally I use a combination of both. I tune idle an part throttle cruise, do some quick stabs, make sure everything looks good, then tune as many ranges as I can get the ECM to see, meaning different loads, an RPM ranges.

The difficult part comes in where AE and PE are involved. AE being based on TPS and MAP changes will add fuel to get the engine to rev up, then PE will add more spark and fuel when the PE is active.

People have discussed disabling either or both of these enrichments, I ten to leave them enabled, though I may reduce them if I feel they are skewing the results.

As far as using the VE2 table or VE adder table, this will use the last cell in the VE and add that value to the value in the VE adder table, at the current RPM.

So if you are at WOT, with a KPA of 100 and at 4400 RPM, $42 will look at the 100 KPA row and 3600 RPM, it will use that value and then add the value in the VE adder table at 4400 RPM, for a final VE calculation.

03-22-2011, 05:01 AM
Hi Juian, glad to see you here.

You will find there's more ways to skin a cat and what Six Shooter outlines them.

What I like to do is get idle and driveability dialed in close so you can drive safely. then ease your way up to WOT on a couple runs and look at tha data.

I do like PE off so I can get all the fuel in there then play with spark.
I have tried closed loop off and works well since you have a Wide Band O2 sensor and get these all close. What are you shooting for on the WideBand for a AFR? With the IH engine a 12:1 would be a good goal to start, don't let it go to lean on WOT. If you can keep it 12:1 to 5000 rpm that will tell you, you have enough fuel presure to go all the way and then go back and smooth it all out. Don't know what cam you have but the IH engine is not a high RPM engine and most cams stay to around 5000 RPM. After that it's just flat do to very restricted ports in the heads. But ypu;ll be amazed at how much tourque they put out around 3000 rpm. HTH

03-22-2011, 08:38 PM
How do I turn off PE and or put it in closed loop?
Not sure what to shoot for on the AFR if you say 12:1 is good, that is what I will tune too.

03-22-2011, 09:35 PM
To turn closed loop off, you would set the coolant for closed loop enable to a higher setting than the engine will actually reach. I usually just max out the setting.

You should be able to set the coolant threshold for PE to a setting above what the engine will see. Using the RPM threshold setting may also work. Like I said I don't usually disable AE or PE, so I'm not 100% sure this would work.

Don't just tune for a number, though 12:1 AFR at WOT is a general rule of thumb, tune for what the engine wants. You may find that you need to be in the 11s or closer to 13s, as far as what the WBO2 is telling you. There are many factors that will affect what the WBO2 reads. If the engine is bucking or feels lazy, you're either too lean or too rich, this is where some use of other senses, being touch, smell and what you see (other than what the datalog is telling) will help greatly. I'm not saying to disregard what is in the datalog, that info is important as well, but it is not the only thing to go by.

03-24-2011, 06:10 AM
Do you guys use Tuner Pro 5?
I am having issues with it logging my WB data. It shows up in the ALDL stream on my APU1, but the information does not play back, when I play back the log file? I have addressed this with Mark on the TP forum, but no answers yet.

Any suggestions?

Being able to see my WB during log playback would really help me! I dont always have a passenger that can relay information for me.

03-24-2011, 11:08 AM
I haven't had time to play with mine much but if I rmrmber correctly in TunerP5 go to tools then AutopROM a/d Data. This will open the window to the extra channels.

03-27-2011, 09:07 AM
I can see the data, but It does not save in the log. I can watch it realtime, but it does not show up in playback.

Not sure why it does this. I could not get any answers on the Tunerpro forum either???

03-27-2011, 12:42 PM
I think tunerPro will save the log somewhere if you close the program?

Open your TunerPro and go to Acquisitions and click on it, then scroll down to Recent Definitions and see what's there and where TunerPro stores them.

03-28-2011, 09:26 PM
It saves the log file, and I can play it back. When I play it back, it shows all the regular stuff (temp, RPM, 02 crosses,BLM's, etc) but it does not show the WB values. Does this make sense?

03-29-2011, 04:06 AM
Only makes sense if you did not add the WB to the ALDL Definition file? That was what I did wrong the first time....

Go to Acquisition and load your Definition file, then go to Acquisition and click on Edit Definition. What I do at this point is save the definition file in another name so if I mess it up I have the original to fall back on. So Save As (Make new name or add V2) Then go back to Acquisition and Edit Definition file again and add a value.

Here's a write up from the Moates site that shows how to add a value, it looks a little different, maybe TPV5 but it has all the parameters you need to enter to add a value to your definition file.
http://www.moates.net/zips/wideband_dat ... ro_lm1.pdf (http://www.moates.net/zips/wideband_datalog_tunerpro_lm1.pdf)

04-12-2011, 07:36 PM
WOT never really seemed to go wide open, if you know what I mean. It would get to the end of VE table #1's RPM limit 3600, then not do much. I thought it was fueling, but I am getting very close to 128 at 3600 and 100 MAP. I finally added the knock sensor, and it acts like a whole new system. Not sure why, or what was going on with the programming, but I installed it, reactivated it in the CHIP, and my motor is running great. I was able to see the knock counts, and faintly hear them after I knew what RPM to listen at. This prompted me to take the timing down in these areas. Timing at 3600 and 100 MAP was also a little high.

Glad I installed the knock sensor. I cant be happier with my $200 EFI system.