when i race my gs i manually shift through the gears at 6000 rpm. recently, while the shifter is in low 1,it will automatically shift into 2 while the shifter is in 1, say 5500 rpm's.its gradually getting worse everytime i take the car out,5300 then 5000 now its down to around 4600 and i cant race the car shifting this low,not tomention i have to click it twice to get it into 3rd gear.first time this happened i accidentally buzzed motor to 6600 rpm's,not happy with that ,need some help.chris
Shifting a THM 400 manually will eventually wear one of the bands out. Is the kickdown hooked up? If it isn't, the trans will typically short shift, and most guys will opt to shift it themselves instead of setting the trans up to shift itself.
larry thanks for your response,you spoke to me at bp weekend at englishtown I GUESS i didnt take it as seriuosly as i should have. years back i removed it because i had no use for an automatic kickdown.i manually shift the car because when im running the car out during time trials i experiment w diff shift points wich is usefull as specially when im allways making little changes,i cant bother always messing w the gov.then when i bracket race i need to shift lower to slow the car down cause it has no cage or ill get the boot(its not gettin a cage its a stage 1 car) i just dont understand how a kickdown switch has control of the valve body on upshifts. i wish you or someone else could explain
hey larry, i just noticed that your et picked up by over .6 sec,is that from the new heads or that you finally got some good rubber out back. cant wait to see i always wanted to know what my car would look like w some nice al heads on it
That was the result of a good leave, thanks to the Mickey Thompson ET Drag radials. My 60' went from 2.1 to 1.84. That got me the 13.220 time slip. The aluminum heads just went on in February. I expect the car to be deep in the 12's at least. I can feel the power increase just driving around normally. I used to be able to ease into it from a dead stop, and then push the pedal to the floor as I got rolling. No more, it spins the tires from a roll, and that's in low stall. It will be interesting to see what she does, I hope I don't grenade the 8.2 rear. The transmission requires 3 inputs in order to determine shift point, and feel. It requires input from the governor (road speed), modulator (engine load), and detent(throttle position). Without all 3 inputs, the trans will not shift optimally. Seems to me, with a bracket car, you want consistant performance. Set the governor up to shift where you want, and hook up the detent switch (kickdown)
The kick down switch activates an electric soloniod in the transmission, which moves one of the valves in the valve body. That valve does two things: One, it causes the transmission to downshift (as long as the governor says it's safe.) and, two, it changes the internal hydraulic "circuitry" that determines the upshift points. I can't get any more specific/technical that that, but that should get you past the mental block.
