Not sure how to post my numerous datalogging files and binary files or I would.
1994 camaro b4c(z28)

I have for a long time been meaning to fix the shift points to work properly with my cam as often times it hits the rev limiter in first, and shifts between 5 and 700rpm too late regardless.

Since this isn't a firebird and I have no performance mode switch, I'm assuming the only table I have to mess with are the normal mode up/down shift points table.

I did the calculations and put in some numbers based on what it shuold be with my tranny and rear end, according to datamaster they were well off and I modified the mph to match the 5500 rpm I want 2nd gear to engage at and 5700 rpm I want 3rd gear to engage with.

The only other thing I'm noticing is the TCC DC (lockup converter) is showing 90% (engaged) pretty much all the time, the "TCC normal mode engage MPH Vs. Gear vs %TPS table shows 255mph engage speed for 2nd gear (should never come on), 40mph for 3rd until 25%TPS then from there to 50%TPS it jumps to 100, from then on its 255, and 4th gear I have it engaging from 0-50% TPS at 55mph and 50-100%TPS it climbs to 140.

I'm using the C.A.T.S. Tuner and datamaster EE

As far as I know those are the tables its working off of, but there are several other tables that have to do with shifting like cruise, performance, kickdown hot cold normal, and a few others, the same with the lockup converter.
My best guess is there is some other data field I'm not changing that needs to be enabled or disabled, or the PCM is pulling data from another table which is why my changes aren't making a difference.

Is there a problem with simply setting the ECM constants enable to 100% and disable to 0% and never having kickdown mode come on? whatever kickdown mode is....?

 

What is the value in the table "Kickdown normal mode shift RPM threshold"?

 

(btw, if you want to hook up the performance mode switch in your car, check out http://www.trifectaperformance.com/t...rmanceMode.htm)

 

There is an ECM Constant labelled
Kickdown Mode enable TPS Threshold = 100%
Kickdown Mode Disable TPS Threshold = 0%

There is a table known as what you just mentioned exactly with
1->2 = 5700 RPM
2->3 = 5650 RPM
3->4 = 5575 RPM

This is the state I just ran it at after moving kickdown ECM constants to those values, before that it was hitting the rev limiter on both 1-2 and 2-3, now it is sporattically hitting 1-2 and always hitting 2-3. the rev limiter is set at 6200RPM

I'm about to review my transmission logfiles for the last 10 minute trial run to see if the speed it was shifting at is still too high, but that's doubtful.

 

You should set kickdown mode enable TPS threshold to 92.6% and disable to 89.5%. These are the factory settings and in my experience there generally isn't a reason to change them. This means "kickdown" mode is enabled past 92.6% throttle and disabled below 89.5% throttle.

What is happening here with the way it is set up is you are in "normal" mode until you go WOT (100%), which enables kickdown mode, and then it stays in kickdown mode until you let your foot off the gas altogether (0%). And it is possible it never comes out of kickdown mode if your off-throttle TPS happens to be 1%.

You should leave your Kickdown normal mode shift RPM threshold values as they are, then set your WOT shift points in MPH in both the Kickdown mode up/down shift points and the normal mode up/down shift points (at TPS 100%) to be the same speed.

If you want to shift at 42MPH out of 1st gear, set the value to 38-39MPH. The values in the tables indicate when the PCM should *begin* the shift. But with a hopped up motor it can rev significantly before the shift actually takes place.

Send me email if you want a sample calibration file that illustrates this.

 

Checking transmission playbacks

I did three or four runs, two I picked out..

first run:
shifted between 5680rpm and 5817rpm between 41 and 42mph, rpm's show continuing to climb but only datapoint is 6012RPM's. 2nd gear in all attempts won't shift without me letting off the throttle a bit.

Last run:
RPM16 was between 5710 and 5858 when it shifted into 2nd at 41-42 mph RPM's continued climbing for 3 data points to 6062 before coming down to 2933 and rising from there again...it didn't change to third gear until 6209 RPM, and althoguh it still shows WPS as WOT, I know it felt like I let off before it changed gears, about 10 datapoints, 3 before and 7 after show it at or past redline during this shifting period, and 80-86 mph region...whichi s higher than I set it at in both RPM and speed.

 

ah, so I shuold pre-set this by a couple mph to get it right, I was giving the computer more credit for being fast than I should....it is possible then that first gear is fixed, and 2nd gear needs to be engaged earlier. I will try reducing by 3-500rpm and 2-3mph and see if that fixes this annoying bug

 

On a stock build the PCM's speed values will realistically be a lot closer to the actual shift speed, but when you have a crazy build the PCM needs a little help. ;-)

You may need to try some different settings to see what works perfectly for you. Your gears, engine power output, transmission build, etc all can impact how quickly the shift actually occurs. On my Impala I needed about 3MPH buffer, with the 3.73 gears and the LT4 conversion.

 

And, yes, 2-3 may need to be engaged even earlier. This is the "slowest" and usually the softest upshift in the 4L60E (has to do with how the accumulators are set up for 2-4 band and 3-4 clutches). My sigs says my transmission is broken - it has a severe flare on the 2-3 upshift at WOT. I had to start the shift 5-6MPH earlier on that one to account for the flare until it got so bad that it bounces off the rev-limiter now.

 

jusging by my EE master data I'm going to need an 8mph buffer and I'm thinking at least 700rpm.

I found the shift timing tables earlier, this PCM has been through PCM4less tune for the engine portion and they did a little to the tranny, so first is 0.75 2nd and 3rd were 6.25, I set 2nd to be 4, should make the 2-3 shift a little quicker


So does it just decide whichever happens first of the kickdown mode's RPM or mph based stuff?
I think I'm going to tune this to run pretty good...and then have a good think about it...
So far every street tire no matter how costly and sticky I shred on the 1-2 shift, slicks wouldn't be an issue.....

So far I'm having a hard time trying to compensate for either my having to stay off of WOT the throttle until above 35mph to keep from wheelspin, and keep it from downshifting when it loses traction during the 1-2 shift at WOT

 

That may or may not make a difference. Bryan did my program, too, and he commanded full line pressure at all WOT upshifts. If he's done this to your program, changing the target shift speed tables won't make a difference. Those tables are used by the PCM to perform adaptive shifting and it adjusts the shift timing by adjusting the line pressure. If you are already at full line pressure the PCM has no way to make the shift execute any more quickly.

 

all fixed, big thanks to vgeglia for giving me a hand and figuring out you needed to pre-empt the computers mph and rpm's.
hopefully this will be easily findable in a search and help someone else out in my predicament

some more information from his emails to help:

The TCC DC data may have more to do with the TCC PWM solenoid then the actual lockup duty cycle. The PWM solenoid essentially “pulses” the TCC on when lockup is commanded to make lockup smoother. Apparently customers were complaining the lockup process was too clunky. So, in 1995, GM added the TCC PWM solenoid to the transmission to address this. My 1994 car doesn’t have it. The reported TCC DC may be the DC of the PWM solenoid.

I have found the reported TCC DC can be inaccurate – it says either 90% or 0% with my car.

There are actually 5 different shifting modes – normal, performance, manual, cruise, and kickdown. Performance is used when performance mode is enabled (e.g. the switch the firebirds had), manual is used when shifting manually with the gear selector, and cruise is used when cruise control is enabled. Kickdown mode is enabled when the “kickdown TPS% enable threshold” is exceeded, and disabled when “kickdown TPS% disable threshold” is exceeded.



By default, the kickdown TPS% enable threshold is 92.6%. So, this means if you press the accelerator past the 92.6% position, kickdown mode is enabled. It stays enabled until the TPS goes lower then the kickdown TPS% disable threshold, which by default is 89.5%. Kickdown is, essentially, WOT shifting. In fact, TunerCat changed the terminology in the version of his tuner for LS1 to “WOT shift speed”.



Once in kickdown mode, it uses the kickdown RPM threshold and kickdown up/down tables to determine shift point. In order to have a shift, the RPM threshold must be exceeded, AND the up/down speed must be exceeded.



In your BIN file, your kickdown threshold is 5150RPM, and your kickdown 1à2 shift speed is 38. This means the shift will be activated if your engine RPM is above 5150RPM, AND your vehicle speed exceeds 38 MPH.



Kickdown Hot/Cold are used as substitutes depending on transmission temperature. “Hot” is above “normal” operating temperature, and “cold” is a transmission that hasn’t warmed up yet.



Normal mode is used in the absence of any other operating mode.