The 700R4 has a lockup torque converter, so be sure and include the wiring to apply the converter clutch. The early models used a vacuum switch and an internal switch in the transmission to provide lockup at the correct manifold vacuum and speed, while later models used a computer circuit and the throttle position sensor to accomplish the lock/unlock cycle. Your 85 should have the vacuum switch system if it's carbureted. If the engine has the electronic-controlled Quadrajet carburetor, it's wise to switch to an earlier model carb without the computer controls for your application. Stay away from the Holley carb conversion most people would reccomend. The Q-jet is a better carburetor, and it's designed to work with your engine. The Holley is a "will-fit" conversion, and probably won't be calibrated for best performance and economy.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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