Cruise Control and Speedometer Cable
Thread Starter
Instructor
Joined: Jul 2011
Posts: 142
Likes: 1
From: Fort White Florida
Cruise Control and Speedometer Cable
My 79 has the cruise control module but the cruise control is not hooked up. I had the car for a few days when the speedometer quit working. The PO had put a 700r4 in it and the speedometer cable from the tarnny to the CC module looks fairly new. The one from the CC into the speedometer looks like the original cable. I was having vacuum leakage problems it seems like they started right around the time that the speedometer quit working.I traced the problem to the vacuum hose going into the CC module. I disconnected the hose from it and plugged it. I have not had a chance to do the drill test on the cables yet but, have a few questions. Does the vacuum going into the CC module have anything to do with the 2 cables and the speedometer? I would like to just bypass the CC module altogether and run a single cable from the tranny to the speedometer. What lenght/type cable would I need to get?
Race Director
Joined: Sep 2004
Posts: 11,874
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
i have the speed control transducer disconnected and removed on my 77..i also have 700r4 ..no problem in using the one piece cable....i think it was a push on at the speedometer end and screw on at the tranny.
ecklers lists it as 1978-82 w/AT without cruise control #A3517 $24.99
ecklers lists it as 1978-82 w/AT without cruise control #A3517 $24.99
Last edited by bobs77vet; Aug 22, 2011 at 04:29 PM.
Race Director
Joined: Apr 1999
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From: CORVETTE 77 385 C.I. TEXAS
The vacuum hoses have nothing to do w/ speedo working. When the cruise control transducer goes out it breaks the lower cable.
A 86-88 MC SS lower cable should connect to upper cable to bypass.
A 86-88 MC SS lower cable should connect to upper cable to bypass.
Thread Starter
Instructor
Joined: Jul 2011
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From: Fort White Florida
Just to be make sure the lower cable will attach to the upper cable with no mods.
Thread Starter
Instructor
Joined: Jul 2011
Posts: 142
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From: Fort White Florida
Cool I will pick one up tomorrow and give it a try later this week when I have a chance to get under the car. Bob I wasn't ignoring your post but, if I can do this without having to get my big hands up under the dash it would be great. Are the autozone one's any good it looks like they have Pioneer and Dorman brand ones?
Burning Brakes
Joined: Aug 2006
Posts: 1,058
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From: Eastern North Carolina
The lwr and upper cables will not hook directly together, if the transducer is still good then you will be fine going that route. There is also a adapter you can buy (if needed) that will replaced the transducer and allow you to hook the cables together.
Le Mans Master
Joined: Apr 2007
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From: Graceland in a Not Correctly Restored Stingray
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Drifting
Joined: Apr 2008
Posts: 1,305
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From: Lewisburg WV
thegazman
Buy a speedometer cable for a vehicle without cruise control. It will connect to the transmission and be long enough to go directly to the speedometer. This what I did. I took out my cruise control as I could never get it to work very well even with a new transducer.
Burning Brakes
Joined: Jul 2008
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From: Canastota Ny
Race Director
Joined: Apr 1999
Posts: 11,520
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From: CORVETTE 77 385 C.I. TEXAS
Cool I will pick one up tomorrow and give it a try later this week when I have a chance to get under the car. Bob I wasn't ignoring your post but, if I can do this without having to get my big hands up under the dash it would be great. Are the autozone one's any good it looks like they have Pioneer and Dorman brand ones?
http://cgi.ebay.com/ebaymotors/SPEED...item35b21afb65
Burning Brakes
Joined: Aug 2006
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From: Eastern North Carolina
Le Mans Master
Joined: Apr 2007
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From: Graceland in a Not Correctly Restored Stingray
Thanks, but I've seen them before. I've also replaced C3 speedo cables before, and seriously considering just going the adapter route when removing the balance of my CC system.
Thread Starter
Instructor
Joined: Jul 2011
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From: Fort White Florida
I cut the crap outta my the palm of my right hand and have 9 stitches in it they come out Monday. So I haven't tried any of the recommendations. I would like to find a source for the adapter. I was able to put a Holley 20-95 Throttle Cable Bracket and a Holley 20-121 Carburetor Kickdown Bracket on my 670 SA carb. I did that this AM carefully and readjusted the TV cable. WOW what a difference. The car used to shift hard and 2-3 shift would not occur until about 3000 rpm. Now it shifts so smooth I can hardly feel it shift and 2-3 shift occurs normally.
Thread Starter
Instructor
Joined: Jul 2011
Posts: 142
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From: Fort White Florida
Update:
I got out there this morning before it started getting too hot and disconnected the two speedometer cables being careful not to bang my palm. I didn't have anyone to watch as I slowly spun the one going to the speedometer but I could feel slight resistance, the one going to the trans spun freely so I guess it is the one that is bad, It will have to wait until I get the stitches out of my hand and have full use of both hands. I also removed the cruise control unit and took it apart. The gears in there seemed to be working properly. I will put it back in when I replace the lower cable and the speedometer should work. When my wife gets home from work I will get her to sit in the car and verify that the upper cable is good but, I am pretty sure it is.
I got out there this morning before it started getting too hot and disconnected the two speedometer cables being careful not to bang my palm. I didn't have anyone to watch as I slowly spun the one going to the speedometer but I could feel slight resistance, the one going to the trans spun freely so I guess it is the one that is bad, It will have to wait until I get the stitches out of my hand and have full use of both hands. I also removed the cruise control unit and took it apart. The gears in there seemed to be working properly. I will put it back in when I replace the lower cable and the speedometer should work. When my wife gets home from work I will get her to sit in the car and verify that the upper cable is good but, I am pretty sure it is.
Race Director
Joined: Sep 2004
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
since the speedo end is a push in unit it may not be as hard as you think under the dash....now the hard part is bending down and playing gumby and getting your arm up under there....so if you are a big guy its definitely a PITA
Pro
Joined: Nov 2010
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From: MA
