Item Subject: cc:Mail Text Virtually all non-electrically activated "automatic" transmissions use a fluidics computer based on valving and pressure and throttle position to determine when to change clutches (gears). Adjusting the level at which the fluidics valves activate (they have springs in 'em to dictate at what pressure they change state) allows you to select your shift point based on rpm by changing the springs. Adjusting the way the throttle input (a measure of throttle position) denies the pressure signal allows you to dictate how throttle position affects shift point. The ratios are fixed of course unless you change the actual drive gearing inside the transmission. What you can adjust is when they change using the model above. The fluidics computer is that really weird looking things with all the passages thats left over when you throw the rest of the transmission in the dustbin. Usta call 'em valve bodies. Al (usta have a BW-65 with 7500 rpm shift points in a non-street gofastgadget) Jim Hall of Chaparral fame coined the term "Clutch, what for?" when developing the automatic for the famous Chaparral racers. Those trannies could handle 1200 HP. Tis rumored ATF coloration is irreversably temperature sensitive to allow monitoring of overheat conditions. But, that was long ago and far away at Rattlesnake Raceway. Al |
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