Im adding cruise control to my car because im lazy, i admit it, and i have just a few questions. I have a 91 RS and i heard somewhere that the car has an electrical speedometer. I know from expierience that on other cars the speedometer cable screws into the transducer assembly and then a cable comes back out to the speedometer. Seeing as this car has the electric speedometer, how do i hook this up, or is their a different kind of transducer for this car. By the way, where is the electric control module for the cruise control system located? BTW, its a 5.0L TBI car, auto tranny. Thanks guys!

 

haven't looked too closely at retrofitting a 91' with OE cruise, but for an 87' thirdgen, one would need:

cruise wiring harness [does not appear to be in thirdgen's unless they came with factory cruise]

cruise control switches [usually on the steering column turn signal/wiper control stalk in thirdgens, time consuming to install since part of steering column must be disassembled to fish wires through column. Berlinetta's have a unique interior and speed control switches may be in an alternate location.]

cruise control servo & mounting brackets

actuator cable that connects servo to throttle body

cruise control logic box. Is a small rectangular black box underneath drivers side dash.

different brake light switch [brake switch has a vacuum hose running into it as a redundant safety device in case electrical portion of switch fails]

vacuum hose

Factory speed control system determines vehicle speed by utilizing the VSS (vehicle speed sensor) inside the transmission or on the back of the speedometer head. All us cars gm has built since the early 1980's have this sensor, since the engine computer needs vss information to accuratetly meter fuel.

Have not investigated parts avaliability lately, but there is a chance some of the required parts have been discontinued and are no longer avaliable from gm.

Perhaps you can locate a similar year salvage yard donor car to get the required parts from. You may have to hunt around a little bit since speed control was not a common option on thirdgens.

As another option, there are numerous aftermarket speed control retrofit kits avaliable, www.jcwhitney.com comes to mind as a supplier. Stay away from kits that require glueing magnets to the driveshaft, these can be troublesome.

 

the former owner of my 83 had after market cc installed in my car. its the most annoying piece of $hit ive eveer seen in a vehicle. i love cc in cars, but id stay away from aftermarket ones. any 90-92 should have similar cc setups. ill be looking for this setup soon if i want to keep my cruise (i have a 92 cluster w/ electric speedo). best place to find it would be the boneyard. her in cali there common to see and find. donno bout there tho.

mike (loomdog)