[70455HOVert]

How well did factory cruise control work back in the day?

Thinking about piecing together a set up for the car, but wondering if at the end of it I'll just be disappointed in the performance of it.

[Lloyd-TX]

Originally Posted by 70455HOVert

How well did factory cruise control work back in the day?

Thinking about piecing together a set up for the car, but wondering if at the end of it I'll just be disappointed in the performance of it.

It worked VERY well indeed. No resume or tap up - tap down feature, but it worked just fine. Usually held your speed better than most modern units, as long as the speedo cables were in good condition.

Had one on my '72 GTO and LOVED it.

[2002Z4CSS]

I used to be a tech at a Olds dealer for 12 years. The GM cruise controls were good units. Kept good speeds even up hills.

[goatless]

Originally Posted by Lloyd-TX

It worked VERY well indeed. No resume or tap up - tap down feature, but it worked just fine. Usually held your speed better than most modern units, as long as the speedo cables were in good condition.

Had one on my '72 GTO and LOVED it.

What Lloyd said! My '69 Bonnie has it and it works every bit as good as the ones on my modern cars- if not better! Simpler to use too.

[70455HOVert]

Ok, good to know!

So in the system, there's a transducer that mounts to the inner fender, gets a speedo cable from the tranny, and then an output speed cable to the dash.

Transducer sends a signal to the vacuum powered dashpot mounted on the engine that has the chain for the throttle, and modulated the throttle movement, and then a switch on the column to activate it, and a switch somewhere to kick it off in case you touch the brakes?

Any pics of the factory setup would be greatly appreciated.

[Steve Barcak]

Yup, they work real well, in fact they are more reliable than the ones used in the late 70s units for sure.

[mrennie]

Were these only available on automatic equipped cars? Years ago I removed a complete setup from a 70 GTO with a TH400, and planned to use it on my Judge with a manual OD tranny.

I'm thinking it should be fine if I add another vacuum break switch on the clutch pedal to cancel the cruise is I push the clutch in, similar to what was used on the brake pedal.

[Terry Gartner]

I always wanted to put the cruise on the stick as well. Hell, I put the cruise on just driving down the street!

[FrankieT/A]

I just installed criuse on my 71 Trans am 4SPD. Works good but has a couple bugs, still making adjustments. I have a 5 SPD on order, so I'll dial in again when that's installed. If any body has questions I'll be glad to answer.

[mrennie]

What kind of bugs? Did you add something to the clutch pedal to cancel the cruise when the pedal is depressed?

Thanks

[Gator67]

Originally Posted by FrankieT/A

If any body has questions I'll be glad to answer.

I'll take you up on your offer! Trying to troubleshoot the cruise control system on my auto equipped 68 Firebird. Should the system hold a speed if the vacuum line from the brake switch is not connected to the vacuum line connecting the regulator to the servo (I have a line going from the regulator directly to the servo without the tee)? Hopefully, my description makes sense. I'm just trying to figure out the source of my problem (I did confirm that the servo will pull the throttle if I connect it directly to vacuum).

[indymanjoe]

I have the cruise controll switch on my turn signal,just need EVERYTHING else now LOL may have an extra if someone wants it,i will have to look though.IIRC the chrome was bad but?....

[FrankieT/A]

Ok, the vacuum line that goes to the brake switch is tee'd off and creates a vacuum leak if the brake is depressed and the cruise control doesn't want to release electrically. It's really just back up safety. You could conceivably put a vacuum cap on it for test purposes ONLY. I never recommend defeating a safety device. However, I am not using a clutch release mechanism currently for two reasons. 1) I'm the only one who drives the car. 2) I wanted to get it up and running before I start fabricating for the clutch pedal.

Bugs: it's a little sensitive. But right now I'm using the vacuum diaphragm (servo) from a Jag because it is much smaller than the Pontiac one. So, I'm making adjustments to see if I can dial it out. If that doesn't work I will try the original Pontiac one.

I, myself am trying to see if it's a manual thing. Remember, manual is gear to gear, while auto's have a hydraulic cushion so to speak.

[Gator67]

Thanks. Then I guess my problem is with the regulator or switch. What's the easiest way to determine the culprit? Thanks in advance.

[FrankieT/A]

Acually, mine came out of a car I was not able to test. So, I bench tested it. I used a 12 power inverter I use to test stereos and such to supply electrical power. Then I used a vacuum pump used to evacuate A/C systems for my vacuum supply, then I chucked a speedometer cable in to a variable speed drill. I actually had it operating on the bench. I could see it modulating and metering vacuum to the servo. At that point I installed it in the car. First test drive it worked, but surged like crazy. Then I started tweaking the adjustments. I have it down to "slightly annoying". LOL But, still a work in progress. I feel I can get the rest out. Maybe by restricting some vacuum or changing the leverage on the throttle.