[Sirrotica]

I have an 86 just like what your 85 is 231 V6 auto. It is the car I'm converting into the NASCAR cup car clone in my signature.

They have an 200-4R overdrive 4 speed and of course as all post 1981 GM cars are Computer Command Controlled. The CCC monitors the O2 sensor and calibrates the primary side of the dual jet carb, It also senses need for air to be injected into the catalalytic convertor via the air pump system to burn the exhaust further and bring the catalyst up to operating temp. It controls the torque converter clutch activation/deactivation via a vehicle speed sensor in the speedometer head. Probably a few other things I'm forgetting that are CCC controlled too.

The car I bought had a rust hole in the oil pan and was run low for oil and spun a rod bearing so you might look at the integrity of the oil pan before buying. The frame rails past the rear wheels was also prone to rust out prematurely on any G body 78-87.