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Old Fri, October 23rd, 2009, 09:45 PM
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F Your Yankee Blue Jeans
 
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The only way I used to drive....even with "tow" tunes that tuners had......was to use the TCS button to lock out 4th gear.

Since I've started tuning for myself and others, the transmission isn't commanded to shift to 4th until a minimum of 57 MPH in the "heavy hauler" tunes since the 3-4 shift is a mutha on RPM loss. Besides that, the 4-3 downshift schedule is set up to closely follow the 3-4 upshift schedule so it downshifts with a lot less accelerator pedal input.

In addition, since the PCM will shift at a pre-determined RPM if the upshift speed exceeds a certain RPM in a certain gear (selectable in the tuning), I set the WOT shift RPM to 2700 RPM in 1-2/2-3 and 3300 RPM for 3-4. With upshift anticipation, the 1-2/2-3 shifts will occur between 2700 and 2900 depending on acceleration rate. Under heavy APP, the 3-4 shift will not occur until the accelerator pedal is released slightly or 3300 RPM is reached.

My towing tunes are set up to mimic a manual as much as possible....only with quicker shifting and no loss of boost.
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Tuning, flashing, burning chips, and repairing all aspects of 7.3L Powerstrokes.
SEVEN 7.3L-powered vehicles in the driveway. Two didn't come that way from the factory!
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