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When you say "got my transmission to shift as I wanted it to", sounds like you mean pretty much unladen.

What GM calls calibrations, are binary files.

Unsure if this is sticky-worthy; very few people have any real use for more than one shift table.
(As a livery driver and driving instructor, a shift table that avoids any enthusiasm helps.)

It'd be nice to see Gary @ Innovative Wiring make a Performance Mode wiring&switch kit.
 

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When you say "got my transmission to shift as I wanted it to", sounds like you mean pretty much unladen.
What I mean is the car came with 3.73 gears. It would hit the rev limiter(fuel cut off) on WOT between 2-3 gear. It would refuse to go to OD then cut the engine in the middle of a high speed pass.

What I have now is a program that up shifts quickly under light throttle but if I go past a high throttle point it shifts aggressively.

It is interesting that I switched from 2.73 to 3.27 gears on another platform and with moderate driving the 3.27 gears give me better fuel mileage in a urban environment than the 2.73.

These are some of the reasons I promote tuning the transmission to one's own driving style and changing the axle ratio before heavily investing in motor modification.
 

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Discussion Starter #23
I soldered in a 2.2k resistor and joined pin 21 & 22, plugged in the pcm and it gave me no codes.
Didn't know all that great info about the performance mode! I probably won't mess with that for awhile though.
 

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What I mean is the car came with 3.73. It would hit the rev limiter (fuel cut off) on WOT between 2-3 gear. It would refuse to go to OD then cut the engine in the middle of a high speed pass.

What I have now is a program that up shifts quickly under light throttle but if I go past a high throttle point it shifts aggressively.

It is interesting that I switched from 2.73 to 3.27 on another platform and with moderate driving the 3.27 gave me better fuel mileage in an urban environment than the 2.73.

These are some of the reasons I promote tuning the transmission to one's own driving style and changing the axle ratio before heavily investing in motor modification.
So long as you're not bouncing off of any rev limiters.

There isn't any city/urban MpG penalty due to more gear. Explains the deeper 1st & 2nd in the 6L80E (4.03 & 2.37), 8L80E (4.56 & 2.97), & 10L80 (4.70 & 2.99).
The highway MpG penalty of 3.73 is barely noticeable under 65MpH.
 

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Any B- or D- car .bin file can have its 'Performance Mode' functionality enabled ONLY by DISabling the 'Force Manual Mode in D2' flag / switch.
Thanks for sharing this info - I don't recall seeing this tidbit before.

Jim
 

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It mimics the function of the 94 & 95 Pontiac Firebird. A normal relatively economical less aggressive shift personality is the default with which we're all familiar.
However, by pressing the button to access 'Performance Mode', a more assertive / aggressive shift personality is accessed and remains in use until the driver intentionally switches back.

Even though GM did not see fit to allow any Caprice, RoadMaster or Fleetwood access to this secondary table, it has been already been populated with some crappy numbers.
However, just as the 'Normal Mode' can be considerably improved upon by reprogramming, so can the original numbers in the Performance Mode table.
Trucks & SUVs make better use of this table more often, although they show it to the driver as Tow-Haul Mode.

As previously stated, each of our cars would need to have hardware similar to the 94 / 95 Firebird Performance Mode circuit switch installed (our cars require longer wiring obviously).

Ultimately, most drivers of vehicles that neither race nor Tow, find that one properly customised table is enough in the vast majority of cases.
 
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