Past basics, commanded shift-points ignored
Past basics, commanded shift-points ignored Posted this on another board as well...
A member of our local F-body club just got a pretty radical project car that was a tune and a stall away from being complete. I haven't been tuning all that long, and this is my first real struggle with a persistent problem.
Here is a mod-list of the car copied and pasted from RPM's board:
Now, the ONLY issue I have left at the moment is shift RPMs @ WOT. Regardless of what I do, the car shifts in the middle 5800s from 1-2 and the middle 6100s from 2-3. Since it is a totally built up tranny, I dumped the tune that was there (that did the same thing) and went back to a stock 99 A4 tune. I zero'd the WOT shift MPHs and have tried an RPM range from 6000-6500 for 1-2 but I still get 5800s at shift. I have worked the MPHs in the part throttle tables at and near 100% TPS as well in vain. The only other item tinkered with is the shift times are all at a 1/4second. I have been from 0 to OEM on these as well. It did the same thing before the stall was installed on Saturday.
Here is the tune: http://frozenwaste.com/Frost/Tune/FBCBRET_Frost_15.hpt
Any ideas at all would be appreciated. Also if there are any other musts for a tranny like this, please let me know.
Thanks alot.
-Steve Williams
A member of our local F-body club just got a pretty radical project car that was a tune and a stall away from being complete. I haven't been tuning all that long, and this is my first real struggle with a persistent problem.
Here is a mod-list of the car copied and pasted from RPM's board:
All Spohn underneath; LCAs, Panhard Bar, SFCs, torque arm
Moser 12 bolt 3.73s
Weld in bar with the door bars removed
Stage 4 built 4l60E with hardened in and out shafts
3200 Precision stall
Walbro pump, relay, and hotwire kit
42lb injectors
Wideband and other guages
Rapid Motorsports built forged 402" LS2 based stroker
Air Flow Research 225 Heads
Comp Cams 236/238 .605" lift 114LSA
Fast 90 intake & Nick Williams 90mm TB, LS6 MAF
All hooker exhaust from header to catback
Full interior, AC, power options.
and more....
Engine has about 600 miles, trans has about 150, the car has about 55K.
Moser 12 bolt 3.73s
Weld in bar with the door bars removed
Stage 4 built 4l60E with hardened in and out shafts
3200 Precision stall
Walbro pump, relay, and hotwire kit
42lb injectors
Wideband and other guages
Rapid Motorsports built forged 402" LS2 based stroker
Air Flow Research 225 Heads
Comp Cams 236/238 .605" lift 114LSA
Fast 90 intake & Nick Williams 90mm TB, LS6 MAF
All hooker exhaust from header to catback
Full interior, AC, power options.
and more....
Engine has about 600 miles, trans has about 150, the car has about 55K.
Now, the ONLY issue I have left at the moment is shift RPMs @ WOT. Regardless of what I do, the car shifts in the middle 5800s from 1-2 and the middle 6100s from 2-3. Since it is a totally built up tranny, I dumped the tune that was there (that did the same thing) and went back to a stock 99 A4 tune. I zero'd the WOT shift MPHs and have tried an RPM range from 6000-6500 for 1-2 but I still get 5800s at shift. I have worked the MPHs in the part throttle tables at and near 100% TPS as well in vain. The only other item tinkered with is the shift times are all at a 1/4second. I have been from 0 to OEM on these as well. It did the same thing before the stall was installed on Saturday.
Here is the tune: http://frozenwaste.com/Frost/Tune/FBCBRET_Frost_15.hpt
Any ideas at all would be appreciated. Also if there are any other musts for a tranny like this, please let me know.
Thanks alot.
-Steve Williams
Last edited by Frost; Jun 12, 2006 at 09:40 PM. Reason: added tune file
I'm wondering whether behind all the electronic
whiz-bang there is an old fashioned harware shift
governor, or something in the mechanicals that
tells the PCM it had better upshift and overrides
our settings.
If you bump the WOT MPH up higher does it refuse to
follow?
whiz-bang there is an old fashioned harware shift
governor, or something in the mechanicals that
tells the PCM it had better upshift and overrides
our settings.
If you bump the WOT MPH up higher does it refuse to
follow?
Originally Posted by jimmyblue
If you bump the WOT MPH up higher does it refuse to
follow?
follow?
-edit-
Oh yeah, if you see anything overly odd in the tune, try not to hang me out to badly
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Verdad Gallardo does the car have stock tire size? i see you are using a 26.1 inch tire for your calcs. from the factory they use a 24.93 for the tire size. it prob wont cause your problem but just something i noticed
Lemme get a log.... the car has MT DRs, tire size is correct... every WOT log is constant wheelspin. It's kinda silly.
while i dig through my tuning laptop I can say now that I'm sure that TPS showed 100%.
while i dig through my tuning laptop I can say now that I'm sure that TPS showed 100%.
Originally Posted by fast98
how about a log. are you sure the tps is going over the 94 percent in order to command the wot tables?
Originally Posted by Steel Chicken
thats the first thing I was gonna ask, on the 05 and 06's GTO's theres some kinda weird issue where sometmies the TPS only reads like 88% even though its @ WOT.
Who built the tranny, and can you find details about any valvebody changes that were done, or changes regarding its electronics? The tranny shop might be able to tell you whats up with the shiftpoints too.
I had a sort-of similar problem while trying to raise the rev-limiter on a 98.
No matter what was tried the limiter still kicked in at the same RPM range.
I found no resolution.
No matter what was tried the limiter still kicked in at the same RPM range.
I found no resolution.
