Billygoatkid

Hi,
I'm using emulator and tuner pro .
i finally got a wideband installed. Question is when car is cold what should I be running on gauge, at idle.
which table controls this?

then at wot what afr number should I aim for and how do you do it?
Would I be doing 4 th gear pulls from 2000rpm up, or what steps suggestions do you have .
mods are 1.6 rr, long tubes, ported plenum , bbk tb, 354 rear Dana 44, etc

thanks

MikeT 90 C4sixer

At cold idle, your WB will show rich for sure, like 12.0-12.8. But dont worry too much about that. There are open loop tables that control the AFR BEFORE it goes into closed loop. The fueling will change quickly as the engine heats up, so i wouldnt worry too much about that.

For WOT, i always shoot for 12.5. Now with stock tables, the calculated AFR is likely to be richer than that. But with the WB you can really dial it in. Start slow, make your WOT runs and log data. Make small changes to lean the AFR......

Billygoatkid

Thank you for the response,

The table I'm adjusting is wot vs rpm , right?

MikeT 90 C4sixer

there are 2 main tables you need to work on for WOT AFR. One is based on rpm, the other is based on coolant temp. they both work together, and calculate a COMMANDED WOT AFR value.

Billygoatkid

So I burned another bin and took it to work. 12.5 - 12.7 wot . Guess I'm on right track. Tables attached

bjankuski

Good job, the 12.5 to 12.7 AFR is what you want to target at WOT and you have it nailed. I am not trying to be critical but I want to point something out. If you want a tune that makes sense by the numbers you would set the power enrichment vs temperature table at 15 to target a 12.5 AFR and then you would adjust the PE vs RPM higher to get your desired AFR. (14.7-12.5)/14.7 is a 15% fuel change and your table is showing a 22.6% fuel change, you are actually commanding the computer to shoot for an 11.4 AFR but you are getting 12.5 AFR.

Since you are actually 8% low on commanded fuel you could add 8% to all of your PE VS RPM tables and set the PE VS temperature table to 15%, this would make the tune appear correct by the numbers. If you did this then you could leave the 262 f and 304 f PE vs temperature table at 22.6 and it would richen the mixture if the car gets too hot and provide you with a safety factor.

I do not want to confuse you but I will also through this out there. You could data log the WOT MAF readings and see what your gram per second reading are and adjust those MAF tables higher by the percentage of error you are seeing. Currently your MAF tables in the higher load ranges are low by 15% (The 8% that you are low on the PE VS temperature table and the 7% you are low from the PE VS PRM table)

These are my observations. As noted by your results there are many ways to achieve the end results you want and as long as the car does what you want who am I to say it is not correct. Have fun (In other words I am not telling you to change anything, I am just showing you how you could make the numbers make sense.)

Billygoatkid

Thank you , thank you!

I follow you until the second part about wot maf data log. I do data log and have some adjustments made with maf tables. But what do you mean by this?
i still think hwymode is on as well because when I let off the throttle it does go lean.
Light throttle is 14.7

I want to do it right and will try what you are saying. this ride to work the car was not up to 100% temp .
the overdrive kicked in so warm up time was over the 3 minutes for the 4+3, and then approx another mile before I tried wot .

bjankuski

In a perfect tune with everything set up correctly if you set your PE vs Temp table at 15% added fuel, you would have a 12.5 AFR at WOT with zero's shown in the PE VS RPM table. Since you are adding (22.6-15)+(7.8)=15.4% additional fuel to get a 12.5 AFR this means your MAF tables are 15% too lean in the positions that you are operating at when you are at WOT. If you adjusted your MAF tables up by 15% you could get the tune closer to what would be considered perfect. That being said this is sometimes more difficult to do and time consuming. If your entire MAF curve is off by 15% then it is not so difficult to adjust but is some areas are fine and some are off then you need to identify and adjust only the areas that are not perfect.

Billygoatkid

Awesome advice!

thank you 😁
Best part is I can try with another bin and keep this one.
whats your take on Hwy mode ? Should I shut that off for logging and tuning right now?
How do I do that.
Today it's nice out and I'm breaking tires loose in second from 2200 rpm and up . Afr is only a little lean below that rpm. Above that is solid 12.5-12.7

GREGGPENN

I partially eluded to this in the other WOT thread for Billy....

Why do you think the AYPY bins (found on the net) default to 22.6% PE vs Temp? Are they really representative of GM's tune?

If so, they only reason I could think of is to allow for fairly significant variance in the injectors they were installing?

When adjustments are stored to create the best BLMs, are those applied to WOT? IOW, when the computer goes "open loop" for WOT runs, is there ANY consideration for what the ECM is seeing during closed loop?

GREGGPENN

I think it's a good idea to leave experimentation of hwy mode until all other tuning is complete. From what I see, biggest "issue" hwy mode should ideally be changed if you swap from gas to gasohol... and/or any percentage of fuel. That's because the target mixture is a static AFR vs a percentage leaning.

To disable hwy mode,
Set Minimum Speed MPH to Enable Highway Fuel Mode to 255.
Set Minimum Coolant Temp for Highway Spark to 300 (304.25).

Billygoatkid

thx

Greg,
coukd you cut and paste what you said from other thread?
I started a new one here because it was getting old and this one is more specific

goat

bjankuski

Listed above are my answers

Billygoatkid

I have seen lean blm at wot when dataloging. Then it adds fuel. But if too rich it stays at 128.

MikeT 90 C4sixer

Not sure about your calculations, but you are making some sense. I plugged in 15% for the 1 table, and 0's in for the other, and the calculation came out to be 12.8AFR. Remember, this is a "Commanded" or "Calculated AFR, not the actual. Is the OP really getting 12.5 to 12.7 on his WB? Now for the actual values from the OP tables, the commanded AFR from 2800-up is 11.29. That's really ok, I would trust your WB. Why dont they match? Good question, but i would get your part-throttle tune dialed in. Yes, take HWY mode out, do some datalogs, and adjust MAF tables for 128 BLMs. Not that easy, takes time. At WOT, the MAF table would be maxed, and not used. Cant recall that part.

Billygoatkid

Hi,
that was on way to work basically checking it out on wideband. At Lunch today same thing, above 2300 rpm.
I'll get more precise with a passenger documenting wot pulls tonight.
Do you guys agree on doing the wot in 4th from low rpm and up?
So it would mean that with tables with previous values I'd be pretty lean up top.
that makes sense as it stumbled and popped, and bucked in the higher rmp since longtubes and 1.6rr

Thx for all the input

Billygoatkid

Hi,
is that highway mode in tables? I only have highway mode spark advance vs load.

MikeT 90 C4sixer

No, dont worry about the tables for HGY mode now. You need to look at scalers to enable the mode. As posted above, just need to set the min temps to enable really high, like 300F. Most stock bins have Hwy mode disabled from the factory....

What year car? What bin and XDF are you using? You may not have the latest one, which might not have all of the parameters pulled out.

What WB are you using? Are you able to datalog the WB AFR into the datastream? It can really show you what is going on with engine!

bjankuski

Mike I believe my math is fine unless the 15% added fuel does not equal lamda .85 which it should. (Lamda .85 is 12.5 afr with gasoline) 12.5/14.7 = .85 or 15% added fuel.

At wot if the maf readings exceed 255 grams/sec then you can no longer use the maf tables to adjust afr and you must use the pe vs. Rpm table to adjust the afr.

MikeT 90 C4sixer

I see how you are using ratios and percents to get the AFR, which is fine i guess. And yes, if your lambda meter reads 0.85, you are 15% rich, and if it says 1.17, you are 17% lean. But i wouldnt really use those ratios to change the fueling. You dont know what fuel he is using, pure gas? Sure stoic is 14.7. Remember the commanded values never = the measured values. I just use the long formulas, and have spreadsheets w/tables to input values and get the calc AFR. I would trust the WB, and adjust the bin to get what you think makes best power AND efficiency.