trans upgrade
it looks like we are going to have to wait to upgrade to a newer MH so I would like to upgrade the Turbo Hydramatic 400 to the 700R trans. Has anyone done this here? Seems at 65 mph its topped out, so...
Forum Discussion
Daveinet wrote:I think I am leaning away from the 700R unless its built and then still maybe notDeano56 wrote:
it would be nice to put an Allison 6 speed in there. I agree with the .75 being a better choice, it just seems like a lot more work with electronics
The TCI EZU controller is about 600 bucks, and does not take more than an hour to install. Its a single harness that plugs into the trans. There is a throttle position sensor that bolts on to the carb, and a wire that goes to the tach. I spent the most time trying to figure out where to screw the module down to under the dog house. As far as programing, that is about another 15 minutes to make it drivable. For the most part, it works right out of the box. After driving it for a period of time, I've tweaked it to shift exactly where I want it to under any condition. And that is the beauty of electronic shift control. You can make it aft exactly like you want it to for the load control, for your specific load characteristic and driving preference. Basically, its just a number that you increase or decrease to change the load sensitivity. You also decide at what point you want the TC to lock up - both speed and throttle position. While this might sound like a lot, the default settings are not bad - pretty close to what the old manual trans would do. But, you can just change it, so instead of unlocking the TC at 30% throttle, you may change it to 40%, just because with the heavier load, it kicks out too often.
If you install the 700R4, you will have to build a latching relay for the TC lock up. Your engage switch must be momentary, so when you tap the brake, it disengages the TC. Secondly, you must mount a switch on the carb, so when the throttle is nearly closed, the TC disengages. These are safety issues, and are NOT OPTIONAL. If you do not, there are certain conditions which will stall the engine, and you loose power steering and eventually brakes. As it turns out, the TC takes a period of time to disengage. If you lock the rear wheels - such as on wet pavement in an emergency, the switch on the brakes does not give adequate time for the TC to disengage, and it will stall the engine. That is why you needs the throttle position switch as well.
