How hard is your Auto's downshift from 2nd to 1st?
11-09-2006, 01:46 AM
#16
Rennlist Member
Originally Posted by DSC928
Thanks all,
I'm not familiar with the parameters of the "dynamic kickdown" so maybe I am describing that incorrectly. At a reasonably slow speed in second (15 to 25 mph) if I depress the accelerator pedal quickly & firmly to say about 3/4 throttle (just short of to the floor) the tranny will downshift to first hard. Then of course it launches like a beast. Maybe it's something I just need to get used to and play with.
I'm not familiar with the parameters of the "dynamic kickdown" so maybe I am describing that incorrectly. At a reasonably slow speed in second (15 to 25 mph) if I depress the accelerator pedal quickly & firmly to say about 3/4 throttle (just short of to the floor) the tranny will downshift to first hard. Then of course it launches like a beast. Maybe it's something I just need to get used to and play with.
Dynamic kick-down:
To make the 928 GTS with automatic transmission a more agile vehicle, a dynamic kick-down has been introduced for model year 1994.
The dynamic kickdown is connected in parallel to the static kickdown. If the vehicle is travelling at more than 34 miles and the throttle valve is more than 24’ open, the dynamic kick-down can be activated by rapidly depressing the accelerator pedal a short distance angular velocity > 240*/s).
If the throttle valve is less than 24’ open and the other conditions are met, the dynamic kick-down is set to standby. If the driver accelerates and the throttle valve is opened to more than 24’ within 8 seconds, the dynamic kickdown is also actuated.
After the kick-down has been actuated, this shift program is held for about 8 sec. and then erased. The dynamic kickdown is also erased if:
-the accelerator pedal is released until the throttle valve opening is less than (24’)
-the throttle valve is closed about 50’ from its maximum opening
-the vehicle slows to less than 34 miles
-the shift point of 4590 rpm in 1st gear or 5950 rpm in 2nd or 3rd gear is reached.
It is not proposed to retrofit older vehicles for economic,reasons. Apart from the throttle valve potentiometer, the engine cable harness and the central electrical system would need to be modified.
11-09-2006, 12:23 PM
#17
Rennlist Member
If anybody is thinking about adjusting (tightening) the Bowden cable to the trans. for first gear starts, make sure your throttle body "butterfly" will still open all of the way up. I had an assistant depress the accelerator pedal all the way to the floor (make sure the gas pedal is actually opening the throttle body all the way up first-adjust as necessary), and then I adjusted the bowden cable so that it would just snap on to the linkage (when pulled all the way out) without causing limited movement in the throttle body. It still starts in second gear if I am in drive, but a sudden depress of about 25 percent will cause a much quicker, and smoother shift to first than before. There is a link that I cannot find that actually covers all of the adjustments to the complex throttle linkage, and in what order to perform the adjustments.
