Sunset01

Have a locally built 4l60e, seems great, but can't get to shift as high as commanded (6400 2-3). In another thread, wondering what effect 'lock TCC on shift' has- from trying both ways and logging, I never see it lock, pt or WOT. Also been wondering whether low trans temps are a factor. Some logs below. Wanted to be able to check line pressure too, but I guess the PCM doesn't know that. (heard somewhere that excesive line pressure can cause the PCM to shift early... though I am supposed to have conservative valve body work). Before I did these runs, I also moved all the mph's down to be more in line with unocked vs. straigh gear calculated mph's. I have 1-2 shift @ 6500, the other two at 6400.

I also find 4th gear locking the converter at 33mph and releasing at about 27mph. Suspiciously close to what 3rd gear is supposed to do, but I have changed 3rd gear engage to 50mph with no change in 4th gear behavior.. this is why I get the slop in the rear rattling around in 4th gear at low speed cruise- the thing is trying to hunker down at 900rpm before it hits disengage.

I also was surging and not idling right after the first batch of runs- logging revealed I was stuck in 3rd !!!? Weird.

All thoughts appreciated.

My edit file : http://www.vettecaliper.com/ls1 (only file in directory)


Log of 4th lockup :

Frame Time RPm Gear Trans temp C TCC lock ?
5841 1061.16 918.8 4 65 YES
5842 1061.34 920 4 65 YES
5843 1061.58 917.5 4 65 YES
5844 1061.76 915.8 4 65 YES
5845 1061.88 921.5 4 65 YES
5846 1062.06 898 4 65 YES
5847 1062.3 897.3 4 65 YES
5848 1062.48 907 4 65 YES
5849 1062.66 911.5 4 66 YES
5850 1062.78 893.8 4 65 YES
5851 1063.02 890.5 4 65 YES
5852 1063.2 905 4 65 YES
5853 1063.32 897.8 4 65 YES


Typical 2-3 shifts:

2691 492.59 1603.5 4 59 YES
2692 492.71 1630.5 4 59 YES
2693 492.95 2160.5 2 59 NO
2694 493.13 3704.3 2 59 NO
2695 493.31 4754.3 2 59 NO
2696 493.43 4876.3 2 59 NO
2697 493.61 4945.5 2 59 NO
2698 493.85 5030.8 2 59 NO
2699 494.03 5094 2 59 NO
2700 494.21 5189.3 2 59 NO
2701 494.33 5295.5 2 59 NO
2702 494.57 5423.8 2 59 NO
2703 494.75 5525.8 2 59 NO
2704 494.87 5629.3 2 59 NO
2705 495.11 5741.5 2 59 NO
2706 495.29 5845.5 2 59 NO
2707 495.47 5954.5 2 59 NO
2708 495.59 6041 3 59 NO
2709 495.83 6132.3 3 59 NO
2710 496.01 5933.3 3 59 NO
2711 496.19 4922.8 3 59 NO
2712 496.31 4781.3 3 59 NO
2713 496.49 4783 3 59 NO
2714 496.74 4802.8 3 59 NO
2715 496.86 4819.8 3 59 NO
2716 497.04 4848 3 59 NO
2717 497.22 4874.8 3 59 NO
2718 497.46 4906.5 3 59 NO
2719 497.64 4871.5 3 59 NO


2826 516.92 2100 2 60 YES
2827 517.16 2193 2 60 YES
2828 517.28 3549 2 60 YES
2829 517.47 3697.3 2 60 YES
2830 517.71 3863.8 2 60 NO
2831 517.89 4435.5 2 60 NO
2832 518.07 4809 2 60 NO
2833 518.19 4901.8 2 60 NO
2834 518.43 4978.3 2 60 NO
2835 518.61 5047.8 2 60 NO
2836 518.73 5123.5 2 60 NO
2837 518.97 5214.5 2 60 NO
2838 519.15 5325.5 2 60 NO
2839 519.33 5433.8 2 60 NO
2840 519.45 5521.5 2 60 NO
2841 519.63 5621 2 60 NO
2842 519.87 5734.8 2 60 NO
2843 520.05 5827.3 2 60 NO
2844 520.17 5924 2 60 NO
2845 520.35 6024 2 60 NO
2846 520.59 6119.8 3 60 NO
2847 520.77 6203.3 3 60 NO
2848 520.89 6257.8 3 60 NO
2849 521.07 5847.8 3 60 NO
2850 521.31 4863.5 3 60 NO
2851 521.43 4804.3 3 60 NO
2852 521.61 4818.3 3 60 NO
2853 521.79 4838.5 3 60 NO
2854 522.03 4863.5 3 60 NO
2855 522.15 4885.8 3 60 NO
2856 522.33 4908 3 60 NO
2857 522.51 4925.8 3 60 NO


STuck in 3rd gear !!:

5633 1023.27 852 3 65 NO
5634 1023.45 615 3 65 NO
5635 1023.57 450.8 3 65 NO
5636 1023.81 318.3 3 65 NO
5637 1023.99 332 3 65 NO
5638 1024.11 270.3 3 65 NO
5639 1024.29 362.3 3 65 NO
5640 1024.53 637.8 3 65 NO
5641 1024.71 1134.5 3 65 NO
5642 1024.83 1421.3 3 65 NO
5643 1025.01 1321 3 65 NO
5644 1025.26 1008.8 3 65 NO
5645 1025.44 726.8 3 65 NO
5646 1025.56 482 3 65 NO
5647 1025.74 392.3 3 65 NO
5648 1025.98 278.5 3 65 NO
5649 1026.1 254 3 65 NO
5650 1026.28 268.5 3 65 NO
5651 1026.52 276.8 3 65 NO
5652 1026.7 499.5 3 65 NO
5653 1026.88 971 3 65 NO
5654 1027 1472.5 3 65 NO
5655 1027.18 1423 3 65 NO
5656 1027.42 1108 3 65 NO
5657 1027.54 800 3 65 NO
5658 1027.78 555 3 65 NO
5659 1027.9 369.3 3 65 NO
5660 1028.14 262.8 3 65 NO
5661 1028.26 259 3 65 NO
5662 1028.44 173 3 65 NO
5663 1028.62 173 3 65 NO
5664 1028.86 173 3 65 NO

samz28

how about iac desired and iac actual during the surging events on flat lands.
Is your odo accurate (have a friend in a nice german car track you )?

I'm going to look at the iac issue and see if the iac is swinging too much to cause the herky-jerkies at low load (ie 0) and flat/downhill sections.

Sunset01

Until I saw the third gear hang, since I am constantly flashing new edit files, I chalked the surging to some relearn. Maybe it still is and the 3rd gear is a fluke. If it persists for a flash that I keep more than 30 min, thanks for the idea, I'll log the two IAC pids. I think I'm good on surging when the thing gets half a chance to learn/adapt.

I think my odomoter is cool, I've checked in past on Parkway mile markers. Also, I test the rolling diameter of my tire to input into ls1edit, with the tire/wheel on the car.

Thanks for the ideas. I'm going to put the 2-3 shift up to 6700 next & see what it decides to do with that!

samz28

please update the thread mines shifting at 6100 where it should be at 6400 (or higher). Strange. i did change my gears to 3.42's from 2.73's and sometimes my speedo is off like in the upper speed range around 85mph its actually around 90mph~ according to a calibrated car.

Black LS1 T/A

I deal with this issue big-time... one of my posts about it is here.

HELP! Short-Shifting out the hole - any ideas?
https://ls1tech.com/forums/showthrea...ht=Short+Shift

Realizing shifting the automatic manually is inconsistent at best, the best I can do to keep mine from bogging down, is to hold mine in gear to about 5-grand and it will shift closer to my programmed shift points (please take the time to read that post... it's pretty detailed, like yours).

If we can do anything to figure out what's going on, I'd LOVe that.

Sunset01

Have you tried moving the RPMs that it is supposed to shift at higher and higher and higher? I'm going to start doing that and see if I get any change at all. I seem to have no reaction to mph too high or low (especially because was originally way too high, as put in #s that didn't account for torque converter slippage). You don't experience the way early 4th gear TCC lockup?

I wish I could monitor line pressure. How much work is done to your trans and how much work in the valve body.. Just because of some saying that the PCM may short shift if it sees (but can it see?) line pressure.

Black LS1 T/A

I've bumped these shift points up to the point that it would hang in gear at lower throttle positions. Since that didn't help a bit, I brought it back to my normal custom shift points. I was trying to see if the part-throttle shift tables might influence things, but it didn't help.

As for the lockup, I have to check that. I believe I am experiencing something wierd, because my car surges a bit at certain RPMs while cruising. I thought misfires detected because of my camshaft might be making the converter lock and unlock, but I disabled low and medium misfires to test that, and it made no difference, so I set it back.

Sunset01

Once a flash 'learns', I'm fairly clear of surging. I did finally drill (3/32") extra hole to get my IAC counts down.. I was idling fine, but IAC was way too high. My throttle stop is fully closed position. You've changed the displacement specification in ls1edit? Did you drill your throttle blade as well?

samz28

black ls1 can you log IAC DESIRED and IAC actual along with timing/a&f while this is occurring.

I'm trying to figure this one out myself. what rpm/load points are you getting the surging? did you use the spreadsheet 1.01 to make sure all ltrims are close to right on at low loads/cruising? Thats what im gonna try first.

In tuning speed density cars we see (interpolation too) that sometimes a cell thats next to another is incorrect. So if cell A, we'll call it has too much timing&fuel it pushes the motor ahead (rpm wise) then cell B is a little incorrect, it causes the motor to rpm down, which then repeats the cycle causing a "herky-jerky" as i call it.

Sometimes ramping (spreadsheet) or just futzing with the numbers and watching whats going on leads to the answer.

mid/big cam reversion can also cause the o2 closed loop system to do freaky stuff. If you can, override the OPEN LOOP and see if the "herky jerky" is still present. This might let you fix the trims (timing/fuel) without having the closed loop system pulling and pushing more gas in.

just a though. there's so many things at work, and with "cell" interpolation you really need to log alot of items to pick up on the issue.

I'm going to look into IAC desired/actual. If the IAC counts are too high, it could be the swaying of the iac opening and closing (trying too hard) that causes the low load "herky jerky". This is the theory i'm going to test first.

If it is so, i might be forced to tweak map or drill hole (tb plate) to help reduce the counts. I think from reading here, the lower the IAC counts (within reason) the less the iac acts as a correction device, and less pendulum swings occurr.

Black LS1 T/A

I'm installing new fuel system. pinning the crank, new pulley steup, re-torqing head bolts, etc. I hope to be driving again next week, and I'll look into it.

Sunset01

Ok, I tried moving 2/3 shift from 6400 to 6700 (and 1-2 to 6800). Only difference in today's testing is it is a little warmer out during the day vs. nite, but trans temps are very comparable. Runs were slighlty uphill, slightly down and fairly flat.
Bottom line- now shift seems to happen right where I want it. Though it is hard to interpret when the scanner reports the rpms still going a bit higher and saying I'm in the next gear.. Maybe it indicates next gear as soon as it is commanded. I don't know if rpm flareup is to be expected during shifts.

Here's a shot in the dark- does my quicker shifting built trans shift quicker than the PCM think it's gonna? Then maybe the PCM is jumping the gun, expecting a slower shift. I have absolutely no codes being thrown.
Be nice to know what is really happening & who knows if I need less/more overshoot rpm in the 1/2 ... & would love to know why my trans wants to lockup 4th @ 33mph. Here's the 3 2/3 shifts I did:

Frame Time RPM Gear Trans temp Lock MPH
794 150.4 4597.5 2 54 NO 47.272
795 150.52 4670.5 2 54 NO 49.76
796 150.7 4736.8 2 54 NO 51.626
797 150.94 4811.5 2 54 NO 53.492
798 151.12 4872.3 2 53 NO 54.736
799 151.3 4934.8 2 54 NO 56.602
800 151.54 5031.8 2 54 NO 59.712
801 151.66 5128 2 54 NO 60.956
802 151.9 5222.5 2 54 NO 62.2
803 152.02 5311.5 2 54 NO 64.066
804 152.26 5424.8 2 54 NO 65.31
805 152.38 5516.5 2 54 NO 67.176
806 152.56 5610.5 2 54 NO 68.42
807 152.8 5713 2 54 NO 70.286
808 152.98 5799 2 54 NO 71.53
809 153.1 5897.3 2 54 NO 73.396
810 153.28 5989 2 54 NO 74.64
811 153.52 6086.3 2 54 NO 76.506
812 153.7 6168.8 2 54 NO 77.75
813 153.88 6256.3 2 54 NO 78.994
814 154 6343.8 3 54 NO 80.238
815 154.24 6429.3 3 54 NO 81.482
816 154.42 6440.3 3 54 NO 82.104
817 154.54 5413 3 54 NO 85.214
818 154.78 4872.3 3 54 NO 84.592
819 154.96 4834.8 3 54 NO 85.836
820 155.14 4847.3 3 54 NO 87.08
821 155.26 4869.3 3 54 NO 87.702
822 155.44 4886.5 3 54 NO 88.946
823 155.68 4913.8 3 54 NO 90.19
824 155.8 4926.8 3 54 NO 90.812
825 155.99 4951 3 54 NO 91.434



2986 545.65 1510.5 4 69 NO 49.76
2987 545.83 1588.3 3 69 NO 49.76
2988 546.01 3109.8 2 69 NO 49.76
2989 546.13 4516 2 69 NO 52.87
2990 546.37 4815 2 69 NO 53.492
2991 546.55 4890.5 2 69 NO 55.358
2992 546.67 4978.3 2 69 NO 57.224
2993 546.91 5052 2 69 NO 59.09
2994 547.09 5154.3 2 69 NO 60.956
2995 547.27 5260.3 2 69 NO 62.822
2996 547.39 5381 2 69 NO 64.688
2997 547.57 5483.3 2 69 NO 66.554
2998 547.81 5610.5 2 69 NO 68.42
2999 547.99 5717.3 2 69 NO 70.286
3000 548.11 5828.5 2 69 NO 72.152
3001 548.29 5929.8 2 69 NO 74.018
3002 548.53 6055.5 2 69 NO 75.884
3003 548.71 6157.5 2 69 NO 77.128
3004 548.89 6268 2 69 NO 78.994
3005 549.01 6355.8 3 69 NO 80.238
3006 549.25 6445.8 3 69 NO 82.104
3007 549.43 6283.8 3 69 NO 83.348
3008 549.55 5069 3 70 NO 84.592
3009 549.73 4866.8 3 69 NO 85.836
3010 549.97 4873 3 70 NO 87.702
3011 550.15 4900 3 70 NO 88.946
3012 550.27 4924.3 3 70 NO 89.568
3013 550.45 4950.3 3 70 NO 91.434
3014 550.69 4980 3 70 NO 92.678
3015 550.87 5004.8 3 70 NO 93.3
3016 550.99 5033.3 3 70 NO 94.544
3017 551.17 5058.8 3 70 NO 95.788
3018 551.41 5083 3 70 NO 97.032
3019 551.59 5117.5 3 70 NO 97.654
3020 551.71 5140.3 3 70 NO 98.898
3021 551.89 5166.8 3 70 NO 100.142
3022 552.13 5219 3 70 NO 101.386
3023 552.32 5140.3 3 70 YES 102.008
3024 552.44 4385 4 70 NO 102.63


4593 835.44 1676.3 4 72 YES 52.248
4594 835.62 1903 3 72 NO 51.004
4595 835.8 2869 2 72 NO 52.87
4596 835.92 4471.3 2 73 NO 54.736
4597 836.16 4925.8 2 72 NO 55.358
4598 836.28 4994.8 2 72 NO 57.846
4599 836.46 5075.8 2 73 NO 59.712
4600 836.64 5173 2 72 NO 61.578
4601 836.88 5290 2 72 NO 63.444
4602 837 5406.3 2 72 NO 65.31
4603 837.18 5505.3 2 72 NO 67.176
4604 837.43 5635.5 2 72 NO 69.042
4605 837.61 5748 2 72 NO 70.908
4606 837.79 5849 2 72 NO 72.774
4607 837.91 5961.5 2 72 NO 74.018
4608 838.09 6065.3 2 72 NO 75.884
4609 838.33 6175 2 72 NO 77.75
4610 838.45 6283.8 3 72 NO 78.994
4611 838.69 6361 3 72 NO 80.238
4612 838.81 6401.8 3 72 NO 81.482
4613 839.05 5337 3 72 NO 85.836
4614 839.23 4877.8 3 72 NO 84.592
4615 839.35 4846.3 3 72 NO 85.836
4616 839.53 4865 3 72 NO 87.08
4617 839.77 4901.8 3 72 NO 88.324
4618 839.89 4924.3 3 72 NO 89.568
4619 840.13 4945.5 3 72 NO 90.812
4620 840.25 4980 3 72 NO 92.056
4621 840.49 4998 3 72 NO 93.3
4622 840.61 5038.3 3 72 NO 94.544
4623 840.85 5058.8 3 72 NO 95.166
4624 841.03 5079.3 3 72 NO 96.41
4625 841.21 5114 3 72 NO 97.654
4626 841.33 5136.8 3 72 NO 98.276
4627 841.57 4403.3 4 72 NO 97.654


Thanks,

Dean

Sunset01

Of course, one big problem with this approach- I have on ocassion shifted as high as about 6350 with the setting down at 6400 (and can have shifted out at 6050 just before)... so I guess I risk a shift happening at 6650 or so with the setting at 6700, as we still have no idea what is really happening.....

samz28

its possible the cpu just doesn't have enough horsepower to control the automatic at those shift points, was the gm ecu ever designed factory to shift so high?

Then you log on top of that, that poor processor is doing alot of work.

I program ecu's and i can tell you there is alot of hacking going on to get them to do what they doing, and NOTHING is dry and cut, if you think your rev limiter is really 6800 rpm's, it isn't. It's about there. When it gets to it. There's always some room for err especially with todays modern cars. Think about this. The M6 ecu has to do nothing with shifting, but its the same ecu, you've now put all these A4 issues on top of the M6 powered ecu and want it to run just as fast?

In a perfect world things would be perfect like that. Maybe you need to overclock the ecu muahahaha

Sunset01

Never though about that, though I get basically same behavior whether I log 5 pids or 15. If I see it shifting at my new high rpms when I'm not scanning, then I'll definitely revisit.... I find the factory tach, at least in my car, surpirsingly on the money. I could see I was shifting right around 6400rpm when I made the last runs & the logs backed it up.
Are other's tach that 'on' , at least in the top of 2nd gear ?

Dean

Sunset01

But of course your argument would expect a late shift if anything.

Dean

samz28

or gm could have compensated this in forethought in software and pre-emptively predict this situation. shift now because i probably won't be able to until the next interrupt/code section appears. As i said programmers hack stuff up to work well. It's not cut and dry. I'd rather program an ecu for safety over power anyday.
hell there could be tables we just dont know about or even more so, calculations, not even tables that affect shifting.

Without disassembling and truly understand the A4 code, you might be missing something really big. This is what separates the map tweakers from the code warriors.

If you ask the (edit/hptuners) folks, how the a4 ecu works, entirely, do they know? Or did they just find all the maps and put them into a spread sheet format to let you edit them? Are there other parameters or equation computing involved as well.

its all black magic except for those who hold AND understand the source code.

on a simple vw ecu, it took me 3 years to truly understand every line of code and its 100x simpler than GM ecu. The emissions was nastiest part. crazy amount of math going on since it did boost and was speed density only. and i'll admit i still dont understand some tables. thank god for rom emulators and good disassemblers

Sunset01

I dyoned yesterday and reported as much as 35hp unlocked with my Midwest 3200/2.0.

I've now got the converter figured out & I think possibly my short shifting issue. I didn't have the cam planned when I first ordered the converter. I am 'blowing through' the converter with the torque/power I am now making. 'verter coming out this weekend and Midwest is restalling for free. Some of my old scanner logs showed how loose this converter acted with my hp- at the top of 2nd gear, my actual mph is about 10% less than predicted by pure tire/gear calculator. It is worst around 5000rpm & slightly better toward 6000rpm- just like the unlocked dyno, which makes perfect sense, torque is dropping off at that point & I am blowing through the converter 'less'. I am confident that my short shifts will clear up too- thinking the computer was confused with almost 10% slippage.