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Hell yes on the wideband rental :thumbs: I just don't want to have to weld in a bung for the sensor :rolleyes:

No need. You can just turn off one or both of your rear O2 sensors (with HPT) and use those bungs for the wideband testing.

 

On the WOT enable (PE enable or whatever HPT calls it) - the base Radix tune sets this at 40%tps. I suspect you would want to do something similar with a turbo - bring in the PE mode before boost starts to rise. Perhaps set it at 80%tps in the lowest 2 or 3 rpm ranges, then ramp down to 40% tps by 2400 rpms or so...

 

It is my opinion that the "Calculated Airflow" table participates in the transient fueling calculation. Since %tps changes can be seen instantly (vs. lag time for the MAF and MAP sensors) this table seems to be the place to figure fueling for rapid throttle changes. However, I do not have any good evidence to support this opinion.

 

:cheers:

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:D Update::

 

New changes:

  • Fixed my IAT table (thanks Deezel :thumbs: ) to not pull any timing until 140* (basically shifted the contents of the stock table pulls to the right).
  • Increased my PE Enrichment from 0.0195 to 0.0215
  • Fattened up my PE (from 1.176 @ redline, to [email protected] redline) --see strangeness below

I now get 0 KR except for the following situation: At 60-65 mph, full wot, IF the truck decides to go into first gear (????) I get 5 KR or so. This KR persists at decreasing levels until I totally come completely out of the throttle. In other words, wot -> downshift to first (three gears) -> RPMs > 5000, 5KR, pull back to 40% tps -> 3 KR, 20% tps -> 2 KR, idle tps -> 0 KR. I tested this a couple of times and held it at 40% to see if the KR would decay, but it doesn't.

 

Plus, with actual timing advance, the trucks leaps forward :thumbs::thumbs:

 

Ambient was 83* this am (heavy cloud cover) so I will have to retest in actual summer conditions, but the increase in timing (from not allowing the PCM to -9* me whenever the truck is running :fume: )

 

Results:

Decreased my average IAT

Decreased my max IAT by 9*

Seems to have decreased my cruise EGT by about 100* (need to verify this -- not logging EGT)

Great seat of the pants dyno torque numbers

 

Next steps:

-Log more full rpm range wots and either take a look at the high rpm timing tables, or reduce the shift point (seat of the pants dyno says I am shifting too high (5650)

-Adjust the PE vs tps to lower than 80 (will step down to 40%)

 

Strange looking stuff:

I was running 1.175 PE as mentioned above. I flashed in 1.199 (redline value) this morning and saw the o2 mvs DECREASE by 30 points (to 850-870 range) or so because of the additional timing. For some reason, at midnight last night, I didn't think this would happen -- maybe I should do my programming a touch earlier :uhoh:

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Strange looking stuff:

I was running 1.175 PE as mentioned above. I flashed in 1.199 (redline value) this morning and saw the o2 mvs DECREASE by 30 points (to 850-870 range) or so because of the additional timing. For some reason, at midnight last night, I didn't think this would happen -- maybe I should do my programming a touch earlier :uhoh:

:eek: Be careful.........

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If you are seeing more timing now, you might have to richen it up even more (maybe PE values in the 1.22 to 1.25 range for hi rpms WOT). Like MN C5 mentioned in other thread - fatten it up until the KR comes down.

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Update to the update...

 

Added more go juice to the PE (erm... 1.2xx sumpthin) and it runs like a two-tailed cat :thumbs: Added two more degrees of timing and wooooooooooo It was a little scary.

 

Total tip in MAX KR is now <4, with most cells < 2 (I think 1 cell was 4, and the rest were 1.6 or so) and very very transient. (5 whole KR cells out of 44000).

 

Daddy likes!!

 

Oh - o2s back up to 880-890. I'm gonna fatten her up another tad tomorrow morning. Dave at STS said the kits run best at 900 (or even a little more and some extra spark), so that's my target.

 

I was actually running the truck a 9* advance with WOT and 1.16 g/cyl :)

 

 

 

Funny story -- after my ride home (with almost no KR at all kinds of WOT conditions), I pulled up to a light near my house. I heard this sickening knocking sound and about dropped my drawers... It was the car next to me in its death rattles ::WHEW:: :D

Edited by TurbochargedBerserker
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And the saga continues...

 

I added even more fuel (up to 1.277 now) and surprisingly had a a bit of KR and was still a touch lean in the first 10-15 minutes of driving and then no more after that :confused: Does the PCM need learn time for PE changes? Damn Ben and his funny white car!!

 

On the positive side, after the initial "warm up" period, o2s were hovering at 898-902 under WOT.

 

Don't touch that dial! The saga continues after this commericial interruption!

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I am not adjusting the IFR (and subsequently LTFTs). BTW, it only takes 50 minutes of part throttle driving to learn the LTFTs.

LTFT constantly change. They never stay the same. Most use a rule of thumb, around 150-300 miles of driving to settle in. BTW, why arn't you using IFR to adj?

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I check my LTFTs 2-3 times a day right now :) They do change, I'll agree.

 

I am not using IFR because I am "done" tuning part throttle. To tune fuel at WOT, you use the PE table.

 

50 minutes is all it takes to for the PCM to learn new LTFTs. 150-300 miles is really really overkill. They never are really done learning, of course, and can change over time, but if you clear your LTFTs after adjusting the VE table or the IFR, then 50 minutes + >20minutes of logging gets you the new values.

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I check my LTFTs 2-3 times a day right now :)  They do change, I'll agree.

 

I am not using IFR because I am "done" tuning part throttle.  To tune fuel at WOT, you use the PE table.

 

50 minutes is all it takes to for the PCM to learn new LTFTs.  150-300 miles is really really overkill.  They never are really done learning, of course, and can change over time, but if you clear your LTFTs after adjusting the VE table or the IFR, then 50 minutes + >20minutes of logging gets you the new values.

I understand how to adj PE for WOT. But my question was, what are your LTFT's doing. Adjustment to VE can effect LTFT's. No matter where you are in the tunning sequence, you always want LTFT's to be 0 to -8.

Edited by m396 #00-011
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My understanding is that PE adjustments have almost no chacne to impact on LTFTs. Since LTFTs are closed loop and properly set up PCMs go into open loop at WOT, I don't see much chance of PE effecting LTFTs unless you are really leaning out the PE table -- even then, you'd only expect the LTFTs that are above the PE MAP enable.

 

My average FTC LTFTs are stably rich (and haven't moved out the range of values I targeted -- -1.5 to -5.5). This hasn't changed since I sdialed in part throttle. Since I was stably rich before tuning PE and since I am not leaning out the PE table, there is no reason to expect the LTFTs to be in relearn mode.

 

That is, unless I've comlpetely missed something (and please explain if so).

 

I am running the stock VE table. Nothing I've ever tried in the VE has had the expected (or even reliable) results with the turbo. VE adjustment definitly prompts an LTFT relearn and requires a reset to speed things along their way. I may end up having to touch this table to account for tip in, but more fuel seems to be working for now.

 

 

Oh and update part tois: Up to 1.297 @ 6k. Steady 900s and no KR tip in or ow from the runs. Unfortunately, the lap top died as I pulled up the drive so no saved logs :(

Edited by TurbochargedBerserker
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My understanding is that PE adjustments have almost no chacne to impact on LTFTs.  Since LTFTs are closed loop and properly set up PCMs go into open loop at WOT, I don't see much chance of PE effecting LTFTs unless you are really leaning out the PE table -- even then, you'd only expect the LTFTs that are above the PE MAP enable.

 

My average FTC LTFTs are stably rich (and haven't moved out the range of values I targeted -- -1.5 to -5.5).  This hasn't changed since I sdialed in part throttle.  Since I was stably rich before tuning PE and since I am not leaning out the PE table, there is no reason to expect the LTFTs to be in relearn mode. 

 

That is, unless I've comlpetely missed something (and please explain if so).

 

I am running the stock VE table.  Nothing I've ever tried in the VE has had the expected (or even reliable) results with the turbo.  VE adjustment definitly prompts an LTFT relearn and requires a reset to speed things along their way.  I may end up having to touch this table to account for tip in, but more fuel seems to be working for now.

I sorry, I was thinking VE, and writing PE. Correct, PE changes shouldn't effect LTFT's. I will edit my post.

 

I can understand were VE changes are trickier on FI. I see many Y-bodys going to different MAF's and such with FI.

 

I kept asking the question about LTFT's because you stated a lean condition. If your LTFT's wern't rich, (as you finally stated they were) this could be a cause. Do LTFT's lock at 0 while your in WOT?

Edited by m396 #00-011
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