Frost

iTrader: (45)

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

Steel Chicken

iTrader: (3)

what tuning software are you using? if its HPTuners load your bin and ill look at it.

Frost

iTrader: (45)

Yeah it's HPT, but I can't up the binary till I get home

foff667

iTrader: (2)

I had the same problem with a built tranny on a stockish car...never got the issues ironed out...would love to hear if you ever get it fixed.

Frost

iTrader: (45)

Here is the tune:
http://frozenwaste.com/Frost/Tune/FBCBRET_Frost_15.hpt

jimmyblue

iTrader: (11)

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?

Frost

iTrader: (45)

Yeah it sure does, but I haven't gone far if any over where it should land RPM-wise for fear of not shifting....

-edit-

Oh yeah, if you see anything overly odd in the tune, try not to hang me out to badly

fast98

iTrader: (16)

how about a log. are you sure the tps is going over the 94 percent in order to command the wot tables?

fast98

iTrader: (16)

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

Frost

iTrader: (45)

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%.

Frost

iTrader: (45)

I don't have the logs here, they are at work. Ironically...

Steel Chicken

iTrader: (3)

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. Id try lowering the 94% in this bin to 85% and see what happens. Nothing else looks odd to me.

Frost

iTrader: (45)

I can lower it back down, but I am dead sure that the logs show 100%TPS during the WOT segments.

SMOKINV8

iTrader: (6)

That's an oddity within the scanner, details here.

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.

white2001s10

iTrader: (4)

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.