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I am continuing to resolve issues with the 1980 L48 vette I acquired.
I am now working on the issue related to the car not downshifting from 3-2 when I accelerate.
Car has the small block 350 and the TH-350 auto transmission. However, the prior owner replaced the manifold and carburetor with Edelbrock components.
My understanding was that the original carb had a linkage that connected to the transmission to trigger a downshift. I no longer see this and the Edelbrock installation manual and videos do not mention how to alter this.
Any guidance on how the prior owner may have accommodated this? The car does downshift sometimes? But not consistently when applying half throttle under 50 mph as it should.
the instructions tell you to use a bracket 8031 or 8036 to install the cables for cruise control or transmission. Did you look carefully and no longer see a cable running down to the transmission. below is the bracket required for the cable http://www.jegs.com/i/Edelbrock/350/8036/10002/-1
Well, it sounds like I am on the right track. Only the accelerator cable and vacuum lines currently attached. I'll have to go look at transmission and see what is at the other end of the "missing" cable. Any idea where I would find it attach to the transmission? I have the service manual, but I am out of town
I have this lightly used Lokar cable that costs $76 at Jegs...Will sell for $20 plus shipping to lower 48. You can also buy a stock style for around $20 at your local parts house I believe.
Well, it sounds like I am on the right track. Only the accelerator cable and vacuum lines currently attached. I'll have to go look at transmission and see what is at the other end of the "missing" cable. Any idea where I would find it attach to the transmission? I have the service manual, but I am out of town
It's attached via a 1/4" Hex Head bolt next to the dip stick tube. Possible a 10mm bolt since you're an 80. Fluid will flow freely if you remove it :-)
Black cable @ 5 o'clock this image
Last edited by jimvette999; Aug 18, 2017 at 08:51 PM.
Well, I got home and looked at the location on transmission where the cable to downshift should be. Plugged! Appears the cable was removed when the carb upgrade was done. Downshifting with gear shift appears to be the solution. Plugged with epoxy! The prior owner did have a shift kit put in, and appears to have decided to remove the cable.
Open to suggestions, bit likely to leave or move this way down the list of things to do.
Well, I got home and looked at the location on transmission where the cable to downshift should be. Plugged! Appears the cable was removed when the carb upgrade was done. Downshifting with gear shift appears to be the solution. Plugged with epoxy! The prior owner did have a shift kit put in, and appears to have decided to remove the cable.
Open to suggestions, bit likely to leave or move this way down the list of things to do.
I seriously suggest that you remove the pan, knock the epoxy out and reinstall the cable......you will enjoy driving it better......it will hold shifts out longer in drive.
Yes...get you a cable....cheap and easy to do. Make sure the bore of the hole is smooooth... don't scratch it cleaning out junk. Later model cables came with a little boot that replaced the o-ring style yours had. The boot will tolerate any scratches in the bore better, especially with some black RTV used sparingly. Hopefully, they left the lever in place inside the cable attaches to. Get a cork/neoprene type pan gasket, flatten pan bolt holes, put gasket on dry...no sealer...don't over-torque. 12 ft. lbs. (16 Nm)... re-torque in a week. cork & neoprene gasket appearance
Last edited by jimvette999; Aug 21, 2017 at 12:10 PM.
I think I will proceed, don't like having to shift manually, (would have gotten a 4 speed if I wanted that)
What linkage is that a picture of? I called Willcox and they do not carry any cables, any suggestions? I just want a stock one to connect to a Edelbrock 1406 (I know I may need a bracket 8301 or 8306)
I think I will proceed, don't like having to shift manually, (would have gotten a 4 speed if I wanted that)
What linkage is that a picture of? I called Willcox and they do not carry any cables, any suggestions? I just want a stock one to connect to a Edelbrock 1406 (I know I may need a bracket 8301 or 8306)
You need the little metal rod you see existing the bracket/lever on the valve body...likely you don't have that piece since the hole is epoxied and that little rod would be residing in the hole the cable goes into.
Can't provide non-supporting vendor links but type in "Automatic Transmission Detent Cable" in search block after entering your vehicle in the AdvanceAutoParts website....or part number Y-100. Part number 8036 is for the bracket at the same joint.
I have all the parts except the little rod that extends out of the transmission housing. Do you know what it is called and where I could but one? Really appreciate all the insights! I also need the single bolt that holds the kickdown cable onto the transmission housing. Would you happen to know the size/thread for these?
Transmission Downshift
