I have logged runs at the dragstrip of my 2-3 shift taking up to 200 rpm more than I had programmed for.
What is the best way to counteract this?
To prevent banging against the limiter I have lowered my shift points and raised the limiter. I'd rather just get the thing to shift when it is supposed to.
1998 Trans Am&&1989 Mustang GT
I have noticed that you have to change all 3 WOT tables and the normal table at 100% and 96%??? TPS. I had to scale all those tables to get it to shift when I thought it should. Originally, I was getting caught with the RPM table being too high from my tuner. Then I was locking the TCC and it was taking the speed too high. So there are several things to consider in this. Good luck. Hope this helps.
Because it must be Brent!&&\'05 FORD F-250 Diesel, baby
Any chance this could be a result of my 3500 stall converter? It's gotta be slipping more than the stocker would.
When I lower just the WOT RPM at which I want it to shift it shifts alot closer to my chosen RPM.
I originally wanted the 2-3 @ 6,000 RPM. The limiter was 6,200. I would bang the limiter a bit and then shift. Then I moved the limit to 6,250 and it would bang a little less and then shift. I left the limit at 6,250 and the shift to 5950 and it would shift without hitting the limiter. But it still seems to "hang" (take forever) to shift when it does.
1998 Trans Am&&1989 Mustang GT
Did you already knock your Shift Adaptation Times down
to something nice, like 0.1 seconds?
It may be the WOT Shift MPH that's holding you back,
the converter lets the RPM slide up more for the same
MPH and every time you improve output HP/TQ, that
amount of "bunge" stretches. You may have to lower
the shift MPH for "windage" and it won't be as much of
a predictable / deterministic linkage as stock, with the
fluid coupling (ATF temp, etc.) variability larger and all.
Look at the shift logs and see if you were below your
MPH threshold when you hit the limiter, or close.
My shift Adaptation is low. It's under .200 right now.
I will try messing with the MPH a bit and see if it helps.
1998 Trans Am&&1989 Mustang GT
Oh yeah. The trans as a whole seems to act up a little
more when temps are above 180.The trans never gets above 210.
I have a deep pan
lower temp thermostat (this actually dropped trans temps by 10*f on average)
I have a cooler but I haven't installed it yet.
1998 Trans Am&&1989 Mustang GT
your shift time is directly prortional to the line pressure during the shift. To get the shortest, hardest shifts you need max line pressure and zero torque reduction during shifts . *BUT* (-big long winded warning goes here-) if your trans is not built to take full linepressure and full engine torque during the shift it *will* break.
200 RPM is not that bad for WOT, on heavy cars out here it is not uncommon to set the shift RPM to 5800 and the limiter at 6200 and occassionaly you will still hit the limiter on a stock trans.
I count sheep in hex...
By full pressure do you mean adjusting the field prepopulated with Max lin pressure which is "90"?
I have not adjusted that but I am starting to move my Base shift pressures vs. Torque vs. Gear up toward 90.
I have a stock trans
1998 Trans Am&&1989 Mustang GT
So Chris, My tranny is built to take somewhere near the 700lbft of torque with all the goodies I could name here.... I have removed all the torque management and set the shift times to 0.. yet, with the turbo, there are times that like 1-2 shift, I have set at 5600rpm and 40mph which is 5600 or so as well, and it will shift around 45 at 6000rpm sometimes. I did not touch the force motor current as you requested... My base shift pressure above 320 lbft is 90 TCC DC line press is 99 over the whole table and offset is near 0. Which of these tables am I doing incorrectly...? or am I just accelerating too fast for the PCM to keep up?
Because it must be Brent!&&\'05 FORD F-250 Diesel, baby
I'm assuming you have a 4L60E.Originally Posted by mustbbrent
When you had the tranny built did you have them do any valve body modifications? I know on the 4L60 the servo feed and bleed-off needed some work.
Also the the 3/4 clutch housing needs work as the centifugal force of the fluid would cause early 3rd apply and binding.
I rely on Transgo for all my tranny mod information.
Does it shift ok into second?
Before you go adding a ton of line pressure and blow a seal, call some trans builders.
Ken
Ken, I have the 4L65E to start with. I have had the valve body upgraded, clutch packs, springs, reaction shell, accumulator piston, billet servos, washers in 1-2, and 3-4, kevlar bands, 3-2 kickdown spring, and hardened output shaft plus some other goodies that I have no idea what they do (he he he.) It does shift nice and very crisp into every and all gears. VERY QUICKLY.
Part throttle is working perfectly (even up to 93-95%TPS,) IMHO, but WOT tuning is way outta whack and I have no idea how to fix it.
Because it must be Brent!&&\'05 FORD F-250 Diesel, baby
Email me your binary so I can take a look.
Also, log some trans data if you can.
Ken
Yes sir. You have email. I included the most recent error in shift in seconds PID.... It gets to 6.3seconds late on the shift???
Because it must be Brent!&&\'05 FORD F-250 Diesel, baby
Did anyone get a resoluton to this?
Since I got my copy of HPTuners I have been soing some serious scanning and have come to the conclusion that with stock converter and unopened engine it is not unusual to see up to 300RPM flare post 6000 before the revs start declining. Its a function of the Shift Command taking time to effect and the rate of pressure rise within the transmission.
Sounds more like your TCC is unlocking during a shift.
300 rpm is just about the slip rate of a non locked converter.
Even after the VCM commands the shift, it will take some time to build enough pressure behind the clutch piston to start the shift. So just start it a little earlier.
These are all the things you never knew existed/happened when the governer controlled the shift
Ken
Well this is even worse now.
I am slipping up to 450rpm when on the spray.
I think I am going to put the TM back to near stock to prevent banging against the limiter. Then I'll get a shift kit.
The car shift around 100rpm within my desired shift point when on motor.
1998 Trans Am&&1989 Mustang GT
If it's clutch slip you are getting, increase the values on the Force Motor table. Don't forget about the max line pressure constant and the 100 column in the Force Motor table. Some calibrations have the 100 column set to 1245ma (minimum pressure).
If it's converter slip while unlocked that's normal.
You may want to incease the TCC offset pressure table.
Ken
What is the TCC DC Offset and base table used for? Online help is non-existant. As a suggestion, could you add some description of what each table does in a future release of on-line help?
Those tables regulate the TCC apply rate range and final locked pressure away from trans line pressure.
Set the base pressure to 100%
Then increase the offset until your slip goes away.
Some people like a firmer TCC engage and set the offset from 90 - 95 %.
Ken
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