Played around tweaking an AMS stage 5 car this weekend. (extremely long)

[PSmalls::DoggieStyle]

BuffaloNogaro spent the weekend here in MI. We spent a lot of time tweaking and logging his setup in an attempt to optimize his setup. On Saturday afternoon, Nick Gustas and his girlfriend joined Joe and me. Otherwise, it was just the 2 of us.

Before tweaking anything, we took some baseline logs to see what exactly we were working with....

02 voltages with no tweaks:


Timing retard with no tweaks:


I only logged 1 or 2 blocks at once so neither of the graphs above include RPM. Both of these are from WOT in 2nd or 3rd gear (I can't remember which were done under what condition, but a majority of them were done in 2nd).

We didn't get a good baseline FATS test block 003 done because of traffic, and it wasn't done until much later in the day, but based on my calculations he was pulling about 550 RPM/Sec with no tweaks at all.

**Note that all FATS test were done later on in the afternoon with only Joe and I in the car. The temperature was very similar, maybe dropping 15 degrees at most. It was between 60 and 75 degrees all afternoon**

Of course, I lost this log among the dozens we did. As far as I can remember, he was pulling slightly under 320 g/s at ~6k rpm, which is where we had to shutdown due to traffic. His timing was abysmal to say the least, with noticeable pull back all over the place and maybe only 1 data point in double digits.

Before tweaking, we also checked his LTFTs; they were all positive #s between 3% and 7%. That along with his low 02 voltages at WOT (in 1 of the graphs above) made me decide to start by adding some fuel....

02 voltages with 10% primary fuel added:


As you can see, not much changed at WOT. However, his LTFTs adjusted to slightly negative #s. The lack of adjustment at WOT stumped us. We then decided to add even more fuel in an attempt to document WOT 02 voltage changes....

02 voltages with 15% primary fuel added:


The first thing I noticed here was that the midrange seemed to fatten up a bit, yet the top end still tapered down pretty low.

After a quick discussion, we decided on pulling a touch of the primary we had just added because it didn't seem to be making a noticeable differece at WOT, yet the LTFTs were quite a bit negative at this point. We pulled ~2.5% back from the 15% added on the last run....

02 voltages with 12.5% primary added:


Because we wanted to richen it up at WOT still, we added some secondary on the next run....

02 voltages with 12.5% primary and 120% secondary fuel added:


As you can see, the WOT 02 voltages didn't adjust much from these changes. We decided to return everything back to default and play a nice practical joke on Joe. Nick and I told him we were putting in some really nice changes and he should cycle the key (lemmitweaks don't take effect until you cycle the key on and off, which you can do while at speed if you have "madd skillz y0") when we say we're ready. Little did he know, all we were doing was reducing SEL to 62%. The look on his face was priceless as he thought we just broke his car. We apologized and told him we were setting everything back to default. Instead, we reduced SEL even more to ~56%. We were laughing our butts off as he tried passing someone on the freeway, but we managed to get a boost log....

Boost log with SEL scaling set at ~56%:


Afterwards, we returned everything to default, and dropped Nick and his girl off so they could go on their way.

The rest of the logs were done wtihout Nick so we decided it was time to do FATS testing, etc.

The first thing we did was the baseline FATS test as I described above. As I already stated above, it was cut short due to traffic and averaged ~550 RPM/Sec.

Next, I added 12% of primary fuel. I thought that was a nice compromise between the fueling settings we had tried so far. After letting things cool for a bit by crusing on the highway, we did another FATS test....

FATS test with 12% primary fuel added:


The car seemd a bit faster than the baseline run. The rpm/sec increased by 30, confirming this observation. We were now seeing 580 RPM/Sec.

I still felt like we need more fuel at WOT so the next FATS test was done with 120% secondary fuel added in addition to the 12% primary fuel added on the previous run....

FATS test with 12% primary and 120% secondary fuel added:


Based on the raw data, it seems as though Joe's car went from the 580RPM/Sec on his previous run to 577RPM/Sec with the added primary and secondary fuel via Lemmiwinks. We didn't calculate this until after the fact, but Joe had commented it felt slower. I think it was all in his head since it is almost impossible to feel such a slight difference, but nonetheless he seems to be correct.

Because Joe preferred the 12% primary added with no secondary tweaks, we compromised and did a log of timing retard with 12.5% primary....

Timing retard with 12.5% primary fuel added:


I then checked his LTFTs and found his part throttle trims to be between -8% and -10%. Apparently, we had added too much fuel in an attempt to richen things up at WOT. I then adjusted the lemmitweaks to only 8% primary fuel added and we did several different logs with this setting....

02 voltages with 8% primary fuel added:


We still weren't happy with the WOT 02 voltages near redline, but the LTFTs settled down to -5% or so and the midrange at WOT was also in the mid .8s which seemed pretty good. Because we wanted to only adjust WOT as the LTFTs seemed just right, we started adding secondary and documenting the results....

02 voltages with 8% primary and 140% secondary fueling added:


02 voltages with 8% primary and 150% secondary fueling added:


Neither of the logs with secondary added seemed to improve the WOT 02 voltages. We were pretty happy with the 02 voltages when 8% primary was added and no secondary was tweaked, so we left his car like that.

Timing retard with 8% primary and 150% secondary fueling added:


It doesn't seem like the extra fuel had much of an impact on the timing retard.

I was quite disappointed with the combination of overall timing and timing correction on this car, but I imagine that is related to the mystery WOT fueling issues. My gut says it is a fuel filter or fuel pump issue, but I'd love to see some other logs from healthy AMS Stage 5 cars.

Joe is now on his way to Portland, Oregon for a rally. He is a crew member for one of the teams and he has the "great responsibility" of driving the rally truck there :P. Therefore, he left his slowgaro at my house for the week :-o

PS-I probably left bits and pieces out. It's hard to remember everything as you can see we spent quite a bit of timing doing this all. All comments and questions are welcome. I'm hoping this will thread will jumpstart a good tweaking discussion. In addition, I'd really like to help Joe resolve this fueling issue, assuming it's not normal to have such low 02 voltages at WOT.

[bagodoosh]

you didn't mention once about your ECUx not working.

are you trying to conclude something AMS related or just general tweaking related?

[Woland]

did you try anything with the multiplicative (inc/dec loads) trims?

[JBear::FATS]

on the AMS Stage V. I do remember that my PT LTFT's were around 0-+2 range. I'm not suprised by your 02 voltages, AMS tuning seems to be a bit leaner than GIAC, I think max power (on 91 anyway) is going to be in the .88 range.

No buildup on the exhaust tips with AMS

[PSmalls::DoggieStyle]

He sat in my car, tried everything he could think of, no luck at all. Erin Watwood at APR has been great to me though and will not give up.

I'm trying to give people some insight into what tweaks should be done based on certain observations so they can use similar logic themselves. I also would like some help diagnosing this car since I firmly believe something is wrong. I would say AMS just won't accept the tweaks, but the tweaks altered everything except at WOT where 02 voltages tapered like there was a lack of fuel.

[B5QShip]

Just a No0b observation, but I agree it seems like it could be a fuel filter/pump issue or injectors maxin' out --> though I assume the Stg5 kit *should* have more than enough fueling headroom.

[PSmalls::DoggieStyle]

Mike Moore has had very good success fine tuning WOT trims with secondary fueling, actually.

I did not play with channels 2 and 3. I wish I had a lot more time to do it. I'm flat out a logging whore!

[(R)S4 SmokedU /-///]

[JBear::FATS]

I've looked over, it does say this. I know on this forum, secondary is usually recommended to add additional fuel at WOT.

[PSmalls::DoggieStyle]

And I can't imagine a software tweaked for 91 octane would be in the low .8s and dipping into the. 7s near redline @ WOT. No wonder it has crappy timing!?!?!?