Hi,

I own a 84 Camaro (Canadian model) without ECU. The engine is a 305 with a quadrajet (without electronic control). Which parts do I need to install the cruise control? If you have a non-cc quadrajet car with cruise control, could you provide me some pictures of these parts or from your engine bay? And maybe vacuum/wiring diagrams?

Also, I want to go to the salvage yard and I need to know if I must absolutely search cruise control parts from camaro/firdbird/trans-am, or if other cars with a non-cc 305 could provide the right parts too?

Thanks

 

There are any number of cars that those parts can come off of. Virtually EVERY GM car from those years (early 80s, generally) had EXACTLY the same cruise setup. The regulators are slightly different, in terms of calibration; since different cars have a different amount of whooma whooma when the cruise tells the car to accelerate (somewhere between almost none and very little), that kind property - the amount that the regulator activates the diaphragm that activates the throttle, and the speed at which it does it, and the speed at which it backs the throttle off as the correct speed is approached - can vary quite a bit. For example I got a regulator off of some Citation or something and put it in my L69 car, and that made it "hunt" something fierce... when the speed fell slightly below the set point it would just STOMP on the gas, then it would let it off to idle after a second or 2 and the car got up to 5 mph over the set point, then it would coast back down, then it would STOMP on the gas... it was unbelievably annoying.

Anyway, you need the vac/wiring harness (all one unit, acoupla vac lines and a handful of wires, all taped up) which includes the grommet where it goes through the firewall; the regulator and bracket; the cable from the regulator to the carb; the 2 speedo cables (1 from the trans to the regulator, the other from the regulator to the speedo itself); the stud thing on the carb; the switch and vac thing that goes on the brake pedal; if you have a 5-speed, the switch & vac thing that go on the clutch pedal; and the turn signal stalk. The cruise stalk comes with the wire that goes down the steering column which you'll have to fish into the column... no small task in and of itself.

It's not particularly difficult to install, but not particularly trivial either. Very tedious and time-consuming to work on any of it.

Be aware that the way they fail is, there's a pair of copper discs inside the regulator, one that spins along with the speedo cable, and one that it induces to move, which is what works the vacuum valve that sends vacuum to the diaphragm to pull on the throttle cable. Very much like the way the speedo itself works, in principle. No moving parts are supposed to touch each other. HOWEVER, as it ages, the little bearings for the spinning disc wear, and eventually the copper discs touch, and when that happens, it pretty much stops working. And worse, it makes the speedo "jump" and destroys the lower speedo cable and often the speedo gears. It was VERY difficult to find one in the boneyard that wasn't already like that 20 yrs ago, last time I needed one; I doubt it has got much eeeeeezyer since then.

I might suggest, look into an aftermarket one instead. They're pretty much a POS, but if you install it in such a way that you can replace it, at least … you can replace it. The factory system is pretty much one-time only and once it dies is VERY hard to repair. I remember back in the 60s putting in ones that used magnets on the drive shaft and a pickup on the trans tailshaft, which obviously dodges breaking into the speedo cable system for example.

 

84 was the first year for the cruise system GM used through 92. 83 was the last year for the transducer and speedo cable driven system. The question is whether a Canadian 84 would have the VSS provisions on the back of the instrument cluster. Being a non-computer controlled car, there's probably nothing in the car that requires a VSS signal, so all that probably needs to be added. Probably easiest to find a vehicle speed sensor that will go between the speedo cable and the drive on the transmission, then wire that VSS to the cruise module. The rest would be the same as any other 84-92.

Get yourself a copy of the cruise control diagrams and troubleshooting sections from a GM service manual for a 84-92 Camaro/Firebird and start studying.

Or, just get an aftermarket cruise control unit and install it per the instructions.

 

After reading this, I'm glad I installed the universal cruise control I got 3+ decades ago from JCWhitney. It uses magnets on the driveshaft and has it's own control module.