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LSX454 swapped 95 BASS burb.

Little lower, little cooler, bigger sounds.
I have an odd turn signal issue too.
The left side is blinking fast as F*** like a bulb is out. But all bulbs are working.

Right side is just fine.

Is there 2 flashers, or just one that controls them both?
 
Keep an eye on the learn table at low RPM, you might have enough cam it has trouble learning at low RPM because of overlap. It may be fine, that cam is kind of in the gray area for self learning at or near idle. If the overlap causes the O2 sensor to see oxygen, then it will keep making itself richer until it wants to die. If not, it will learn like normal. See if it gets better or worse. If it gets worse, delete the left side of the learn table and don't let it add fuel below a certain RPM.
 
Yeah I went to the learn table the other night and right around idle area it was trying to pull like 40 from every square.


I did a couple hard pulls.. not sure if I was supposed to wait longer or not, but just a couple 0-60, 40-80ish?, floored.
Datalogged them.

So far,
It won't do a standing start burnout:notworthy:. Yet:waytogo:
The rec port heads and bigger cam DID affect power below 3500 or so. Noticably. (Expected, but surprising)
Above that.... DAMN! Lol.
Drivability with the 3000 stall is entirely normal.
Almost like not really a stall lol.
Never driven with one before. But my 880 RPM idle will push me down the road on flat ground. Didn't expect that. Lol. I figured I'd have to get to like 1800 before it'd move out.
First gear shift, lollygagging through an intersection will jar your teeth out. Rest of the shifts have been quick, precise, and clean, but smooth. First gear was hard before, but it's harder now lol.
 
So... Base fuel tableIMG_20240920_182429142.jpg

Current learn table...
IMG_20240920_182418481.jpg

Is that little orange spot in the idle area what you were talking about?

I was going to transfer the learn table to the base fuel, but didn't want to mess up that area is that orange spot is a bad thing lol.

I did go into my learn and set RPM to start learning at 950 just now.
 
And.... First dead stop hard takeoff it squeaked the tires, then sorta just sat, then took off again...

Did the same thing coming in to work tonight :dunno:

IMG_20240920_175649521.jpg
 
I did some digging and seen that at the instant I smash throttle the AF drops way down, then the rpm falters....
A while back I was playing with acceleration enrichment and ran it up a bit.

I'm wondering if it's flooding out for a second:dunno:

Light blue is AF ratio.

IMG_20240920_215100337.jpg
 
Also noticed that the AF stays roughly 13.6-13.9 almost always.
Few random moments here and there. But no matter what the target AF is, it always stays there.

No idea if that matters, just found it curious lol.
 
If it's fueling from the base table + the learn table, it has calculated some of your VE's in the low 30's. It's saying that your cam/head swap cost you 25% efficiency down low and picked up half of that up top. It's probably gaining more than that up top in reality, because your base table is kind of exaggerated/safe. It shows VE increasing all the way up, as though the engine's torque peak was above 7000RPM. It was probably a way to ensure it was super rich up top as a place to start tuning.

I think the fact it has pulled so much VE/fuel around idle and that the idle stabilized means that it didn't go down the wrong path. I think the concern was that it would misfire from a rich mixture, as your starting VE would be too high with the new parts. Once you get rich misfire, the ECU can follow the O2 sensor's lean reading and keep adding fuel until it doesn't run at all.
 
I kind of think it's lean all the time.
I've never been great at the AF stuff but I always thought you wanted 12-13. I'm running 13.5-14.7 pretty much always. No matter what my skinny pedals or target AF is doing.

That because it's still learning?
Later I'll try and get a screen shot of a data log on here.
 
Not exactly a screen shot, but,... See how the AF (light blue) is basically straight across the screen, even though the yellow is my target AFR.

Not sure if any of that matters because I'm EFI stupid. But it seems like it's not really paying attention to the target.

IMG_20240921_204209725.jpg
 
I put the acceleration enrichment back to Holley's stock ramp.
It seemed to help the foot smash fall off that it does. It was shorter. The red shows that early flat spot.
 
I kind of think it's lean all the time.
I've never been great at the AF stuff but I always thought you wanted 12-13. I'm running 13.5-14.7 pretty much always. No matter what my skinny pedals or target AF is doing.

That because it's still learning?
Later I'll try and get a screen shot of a data log on here.
Why do you want 13.5? Without other reasons, running at stoich is good for all of your part throttle cruising. For gas that's 14.7. If you run E10, it's more like 14.1. From the factory, these engines even idle at stoich. With a bigger cam, you'll have to just figure out how much fuel it likes to idle well. However, I don't think the ECU actually knows AFR. From what I see, the Terminator comes with a WBO2 and what those measure is how much oxygen is needed to reach stoichiometric combustion (i.e. Lambda). Somewhere you have to tell it what kind of fuel you're using for it to convert that O2 feedback into a calculated AFR #. 13.5 or 13 would be only for high load.

Why doesn't it aim for the target? I think it does. I think the main reason you're seeing an "issue" is that you have those two parameters on different scales in your plots. Through the middle of your last shot, the target is ~13 and the AFR is ~13, so :dunno:, but I think you just need to scale them the same. When it's not learning towards the target, there must be a modifier somewhere. Usually there's a table to add fuel during warmup, based on the ambient conditions, from the fuel composition sensor (FFV), etc. In a factory ECU, there must be 40 things that affect fuel and timing apart from the base tables.

Keep in mind that your tables have a finite resolution. 31x31 is HUGE, but you're still rarely using just a single cell for your fuel, it's interpolating between them. So as it learns at one operating point, that slightly changes the operation at nearby points. The engine needs don't change very quickly with MAP/RPM changes, so this should be plenty of resolution. An engine is just not going to read exactly at target AFR all the time, especially with transient conditions. All EFI is like that, it's just that ignorance is bliss :D
I put the acceleration enrichment back to Holley's stock ramp.
It seemed to help the foot smash fall off that it does. It was shorter. The red shows that early flat spot.
A quick lean blip is normal on a throttle stab. The acceleration enrichment is to reduce it, but not really wipe it out. Factory LS rates are a good starting point (some people never change that), but in the end it's kind of a feel thing. I'm not sure the lag is reduced in the plots, you've just cut the time scale in half for the plot.
 
I see the scales thing now. I was reading the target scale as the actual AFR.:waytogo:

It's getting a quick rich blip. Like 10 instantly. Truck falls on its face, then AFR comes back and away I go.

Why I expected 13ish is because all the old dudes I grew up with always talked about 12.5-13 as good.:dunno:
Never really researched it because I figured they knew their chit lol.
 
I thought 14 was super lean and would kill the engine.
 
12.5-13 would be for WOT as it’s kind of a sweet spot for max power NA but it’s still general. Cruising is closer to 14. From my limited knowledge, it looks like you just need to keep driving it and letting it do its thing for a while before you start tinkering on it.
 
Set the afr, drive it and watch the target vs actual afr and the closed loop compensation. Watching the learn table will also show the percentage it’s adding or subtracting.
 
Why I expected 13ish is because all the old dudes I grew up with always talked about 12.5-13 as good.:dunno:
Never really researched it because I figured they knew their chit lol.
12.5 is pig rich unless you're in the top few rows of your table. It will foul your plugs at idle and make smoke.
I thought 14 was super lean and would kill the engine.
I've had my TPI setup cruising at over 16:1. No need to drown it in fuel under low load conditions. If you don't know anything about the engine, you'd usually set most of the target table to 14.7 to start. That's the chemically correct ratio for gasoline.
 
Through the middle of your last shot, the target is ~13 and the AFR is ~13, so :dunno:, but I think you just need to scale them the same.
A WBO2 can only read about 10:1 - 19.1 (gas), so starting the scale at 2 doesn't do anything for you except keep the AFR line from taking up too much space on the screen.
 

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