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727 shifting question- UPDATE !

Posted By: tippytoe

727 shifting question- UPDATE ! - 06/14/12 07:15 PM

I have a 70 Dart that has an early 70's 360 and (year unknown) 727 trans. Trans is stock, engine has an edelbrock 1406 carb & performer intake. When I got the car, I neglected to notice someone had removed the kickdown linkage. I borrowed a smallbock kickdown setup from a friend & I can not get the shifting points to change. The car's 1-2 shift is at 20 mph ( a little late) & the 2-3 shift is at 47 mph (very late IMO). I have tried adjusting the kickdown linkage from one extreme to the other (and all points in between) but the shiting points do not change at all. I am starting to wonder if the trans itself might have problems. Any one ever have the same issue or have an opinion ? I am out of ideas.

Attached picture 7250214-screweddeal.jpg
Posted By: JohnRR

Re: 727 shifting question - 06/14/12 07:21 PM

Your first problem is the linkage that connects to the carb throttle stud. Until you have the end of the slot closest to the firewall up against the carb stud at idle no amount of adjustment is going to change a thing. The kickdown linkage has to start moving as soon as the carb throttle does thru the entire range of motion of the carb linkage .

It appears what you have is 2 bbl linkage connected to a 4bbl , that top piece is not the same 2bbl to 4 bbl .
Posted By: tippytoe

Re: 727 shifting question - 06/14/12 08:42 PM

Quote:

you have the end of the slot closest to the firewall up against the carb stud at idle



That is originally how I set it up, but the 2-3 shift wasn't until 55 at that setting. It shifted a little better (47 mph) when the linkage had some slop at the throttle stud.
Posted By: tippytoe

Re: 727 shifting question - 06/14/12 08:48 PM

Quote:

It appears what you have is 2 bbl linkage connected to a 4bbl , that top piece is not the same 2bbl to 4 bbl .



You are correct, it is a 2 bbl linkage I am trying to use. As far as "top piece", I am not sure what you are referring to. Are you talking about the linkage rod itself, or something else ?
Posted By: John_Kunkel

Re: 727 shifting question - 06/14/12 11:43 PM


The top piece is the rod that the slotted end screws onto, Edelbrock makes thread extensions for it so the rear of the slot will contact the rear of the carb stud at idle.
Posted By: tippytoe

Re: 727 shifting question - 06/15/12 01:29 AM

Quote:


The top piece is the rod that the slotted end screws onto



Ok, I understand what you are referring to. The picture I posted was taken when I finally gave up. I started off the adjustment with the rear of the slot contacting the throttle stud at idle, like John RR suggested. It actually shifts better (2-3 at 47 mph) in the pictured position than the correct position John RR mentioned(2-3 at 55 mph). That is why I am wondering if I don't have some internal transmission problems (shifts better with kickdown adjustment wrong than when its adjusted correctly).
Posted By: tippytoe

Re: 727 shifting question - 06/15/12 01:38 AM

FWIW: Don't know if this sheds any light on my problem, but the trans also downshifts awkward. The 3-2 downshift is at 40 mph & the 2-1 downshift is at 25 mph. In both cases, the car slightly nosedives & revs up like an improper downshift on a manual trans.
Posted By: MoparforLife

Re: 727 shifting question - 06/15/12 02:56 AM

Here is a variant of the linkage. Need to have the spring 13 hooked to the linkage belcrank to pull the rear of them linkage slot forward to have constant contact with the throttle pin for the full travel of linkage beginning when the throttle starts to open and all the way back. This is what governs the throttle pressure to for correct shift points.
Posted By: Dads426

Re: 727 shifting question - 06/15/12 05:44 AM

With the linkage disconnected at the carb you should be able to pull the kickdown lever on the trans fully forward so that when the linkage is reinstalled on the carb stud it will be at the rear portion of the slot, as shown in the previous post. The spring should exert forward pressure to keep the linkage tight against the carb stud so that when the throttle is opened the linkage moves and pushes the kickdown lever on the trans to the rear. These adjustments are done at curb idle (not fast idle).

If the trans is an 80's 727 they have a problem with the front clutch pack seal failing which causes a late 2-3 upshift. This can be detected in the car by pulling the valve body and doing an air test.
Posted By: John_Kunkel

Re: 727 shifting question - 06/15/12 07:29 PM

Quote:

That is why I am wondering if I don't have some internal transmission problems (shifts better with kickdown adjustment wrong than when its adjusted correctly)



Easiest way to tell is to temporarily disconnect the linkage at the transmission lever and pull the lever full forward; it should shift way early with the linkage disconnected, if it still shifts late the problem is internal.
Posted By: tippytoe

Re: 727 shifting question-UPDATE - 06/21/12 01:49 AM

Quote:

Easiest way to tell is to temporarily disconnect the linkage at the transmission lever and pull the lever full forward; it should shift way early with the linkage disconnected, if it still shifts late the problem is internal.



This is why I posted the question. I hadn't even thought about trying that.

UPDATE: I performed the test above above & sure enough, the transmission shifted way early like it was supposed to. I also may have found the real root of my problem (which leads to another question). When I was under the car disconnecting the linkage from the lever, I noticed the kd lever on the trans cant come all the way forward with the linkage connected. The pivot that mounts on the trans can not go any farther but the kd lever still needs to come forward another 45 degrees.

Question 1: Is the kickdown linkage (kd lever, rod, pivot) at the transmission different from a 904 to a 727. The car has a 727 but the linkage is exactly the same as whats on my 904 setup on my 70 Coronet.

Question 2: Approximately where is the kickdown lever at (based on clock position) when it is all the way forward (toward the front of the trans) ? Here is why I ask:

When the k/d lever is all the way forward (released) on my trans, it is approximately in the 10 o'clock position (assuming you are standing directly over the transmission, looking down). My buddy's trans fully released is in the 9 o'clock position. Makes me wonder if the lever ( or shaft it mounts on) has been messed up & is the root fo my whole problem.

Any info & opinions would be greatly appreciated !
Posted By: marks69

Re: 727 shifting question-UPDATE - 06/21/12 02:43 AM

Consider this a bump. You could buy a camaro to drive and that would fix it. LOL.
Posted By: dan9

Re: 727 shifting question-UPDATE - 06/21/12 04:02 PM

Are you sure you don't have the pivot reversed at the bellhousing area? I think it can go on 2 ways.
Posted By: 68jim

Re: 727 shifting question-UPDATE - 06/21/12 07:04 PM

Maybe not the best picture but I was fitting all of my brackets, clips etc for this 426/727. My rod from the trans clocks around 6 and the hole for the rod up to the throttle bell crank is about 9.

Jim

Attached picture 7259482-transmission3.JPG
Posted By: 68jim

Re: 727 shifting question-UPDATE - 06/21/12 07:16 PM

OK, so I reread your post and I thought you were talking about the lower bell crank positioning. I see now you were talking about the lever on the valve body. Someone else with more transmission experience can talk about different levers from other car/truck models but the levers are keyed and only go on one way. Although I could see where maybe one had been drilled out for some reason years ago...or could be drilled out as a possible last ditch fix...
Posted By: John_Kunkel

Re: 727 shifting question-UPDATE - 06/21/12 08:29 PM


Many 727/904 linkage parts aren't the same and a mismatch of parts is a common cause of your original problem...that's why I said to disconnect it at the trans lever for troubleshooting.

There are so many engine/trans linkage combos over the years that it's hard to say what's correct, best way is to procure the entire linkage from an unmolested car with your same engine and trans.
Posted By: tippytoe

Re: 727 shifting question-UPDATE - 06/21/12 10:12 PM

Quote:

There are so many engine/trans linkage combos over the years that it's hard to say what's correct, best way is to procure the entire linkage from an unmolested car with your same engine and trans.



That's what I was starting to conclude. Since the car isn't a matching numbers show car, I have decided to just scrap the whole linkage setup & go with the Lokar kit & be done with it. I went to a buddy's place (Marks69) yesterday & he showed me the setup on his car. I think that would be the quickest, sure-win fix. My Dart is one of those "wish I would have never bought this POS" vehicles, and I need to get it back on the road ASAP to give me a more positive attitude for the car. Working on something you love is one thing , working on something you despise is the extreme opposite .

I wanna say thank you to everyone with their input (it helped alot).

Attached picture 7259721-1970darttrade003.jpg
Posted By: John_Kunkel

Re: 727 shifting question-UPDATE - 06/21/12 11:28 PM



With the Lokar you could be back in the same situation if you follow their adjustment instructions. You need to measure the full travel of the carb lever where the cable attaches and then measure the full travel of the transmission lever where the cable attaches; it usually won't be the same so you need to drill a new hole in the transmission lever so that the full travel of both levers is the same.

There should also be a spring pulling the transmission lever forward.
Posted By: tippytoe

Re: 727 shifting question-UPDATE - 06/22/12 12:33 AM

Will do ! Thanks for the info !
Posted By: tippytoe

Re: 727 shifting question-UPDATE - 07/22/12 04:44 AM

FINAL UPDATE:

Removed the mismatched factory garbage & installed the Lokar kit. Car shifts great & couldn't be more pleased !

Thank you for everyone's input.
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