Trans shift points?

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g49bridges

g49bridges

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Wondering if there’s a way to adjust my shift points.... I’ve got a 74 Duster I dropped in a 340 and a new 727...aftermarket everything. Running a lokar lockdown and a quickfuel carb. Car runs and drives great, but shifts early and I wish it would kick down a little quicker. Was wondering if this is in the cable adjustment? As is, it has about 1/16” slack with no throttle.
 
I'm running the Lokar cable with my 408/727. First, I made sure that there was no slack in the cable and that the travel in the carb lever matched the travel in the tranny throttle lever so that at idle the tranny lever was full forward and at WOT the tranny lever was all the way back. I then made adjustments with the adjuster nuts up at the carb end of the Lokar cable, lengthening the cable sheath 1 thread ( 1 revolution of the nuts) at a time until the shifts dragged out to where I wanted them. I put dots on the 2 adjuster nuts with a paint pen so I could tell their position when adjusting. It took me 6 full turns to get it 'just right', but only 1 turn at a time then road testing.

I also put a light return spring on the tranny throttle lever pulling it forward. That seemed to help as well.
 
Thanks for the info. As of right now my trans lever is matched to my throttle....all the way up at idle and all the way back at WOT. So I need to take slack out at the adjuster but to raise the shift point, or add more slack?
 
This will only affect your part throttle shifts. To change WOT shift points you will need to change or modify the governor weights. A&A trans sells weight kits for different RPMs.
 
To be clear, your WOT shifts are golden, but the part throttle shifts are too early? In high gear before you cross the intersection?
 
I put manual valve bodies in all my cars. Unless i lose the use of an arm or something, I'll NEVER go back to auto function.
 
g49bridges said:
Thanks guys. And yes, I'm only looking to adjust the part throttle shifts. It does great on WOT.
Click to expand...

Here's what I've done for years...
TVpreloadb.jpg

On your VB, turn in the large flanged screw (Red arrow) to take up the clearance marked in blue.
Tighten until there is 0 lash felt against spring pressure on the Throttle Valve (green arrow), then turn in an additional 1/4 - 3/8 turn.
This puts 'preload' on the TV spool, forcing the Governor pressure to rise a bit, so that the shuttle valve doesn't just snap over causing a low Governor pressure shift.
It's a simple fix but, you do have to drop the pan. This bypasses the trial and error with the governor wts.
I don't suggest going to a half turn, cause it will hold 2nd until about 3000 rpm.
 
BTW
This IN NO WAY affects your WOT shift points..
 
Mine shifts to 2nd gear too early, both at partial and full throttle. It barks the tires into 2nd even at low rpm. It shifts to 3rd perfectly at full throttle, and maybe just a shade late on the street. But I can live with that.

It's the shift to 2nd too early that bugs me.

I adjusted the cable, and it pushed both shift points a bit higher, but the shift to 2nd is still too early and I don't want the shift to 3rd any later. So I won't adjust the cable any further.

What am I looking at?


7milesout
 
7milesout said:
Mine shifts to 2nd gear too early, both at partial and full throttle. It barks the tires into 2nd even at low rpm. It shifts to 3rd perfectly at full throttle, and maybe just a shade late on the street. But I can live with that.

It's the shift to 2nd too early that bugs me.

I adjusted the cable, and it pushed both shift points a bit higher, but the shift to 2nd is still too early and I don't want the shift to 3rd any later. So I won't adjust the cable any further.

What am I looking at?
Click to expand...

I suspect you have a spool hanging up, or a broken spring in the VB, for just 2nd to be effected like that. I assume a shift kit has been installed, OR Line Pressure has been raised, due to the barking 2nd scenario.. :)
That stated, the MOD I outlined in the previous entry/picture may not be the way to go about this. Mainly because some (TransGo) shift kits have provisions to delay 3rd in the kits programming. So, while the 2 gear shift will be raised, your 3rd gear shift rpm will be made higher than it is currently.
TransGo and Sonnax has kits available to remedy Throttle Pressure related problems. I prefer the TransGo kit # TF-TV cause it also addresses a loose TV bore issue.
TransGoTFTV.jpg

available under these suppliers part numbers:
Common Distributor Part Numbers:
Transtar T22741NBK
WIT Whatever it Takes A12749N-1K
Natpro K12887D
PDQ TG-TF-TV
PTW Portland Transmission Warehouse TF-TV
Dacco, MST, D&E, and Dean TF-TV
OTS Oklahoma Transmission Supply TF-TV
A & Red's TNS-TF-TV

The Sonnax kit only addresses shift points, not bore wear, and comes with 2 springs w/ shims. That's a nightmare.

I've seen Check Balls try to drive themselves through the separator plates cause problems too. Especially on our phord counterparts..

Unfortunately, it looks like your VB will have to come out, disassembled, and inspected.

OR, replace it with a known good one. Hopefully, you have the abilities for this, or know someone competent who can that won't gouge you..
 
After re-reading my post, I was not exactly clear.

Focusing just on my 2nd gear shifting:
  • At just normal acceleration, it shifts (to 2nd) very nice. Not harsh, not sloppy. Very crisp. It just does it sooner than I think it should. I'll try to notice the rpm, but it's probably in the very low 2,000's range. I've rather it be more like 2,500 rpm.
  • At full throttle rpm, I'm going to guess it shifts to 2nd at like 4,500 rpm. It's at that (relatively) low rpm and full throttle that it will bark the tires. I consider the tire barking normal. I just wish it would shift at 5,000 rpm versus 4,500 or so. It's difficult to know the rpm at full throttle because a) you know, the driver is kind of busy, and b) the tach seems like it doesn't like to move quickly, and it seems to lag and not be accurate when at full throttle.
In the quarter mile, my car runs across at about 5,000 rpm @ 97ish mph. That's why I would like the 1st-2nd and 2nd-3rd shift to shift at 5,000 rpm. But at full throttle, the 1st-2nd shift is probably 4,500 rpm, and the 2nd-3rd shift is probably close to 5,000 rpm. The shifting firmness is just right in all cases (cruising and full throttle). So, until it will shift at the correct rpm, I just hold the car in L1 until 5,000 rpm … same for L2, until 5,000 rpm.


7milesout
 
Ok, what you're describing to me, is pretty normal. Try tightening the cable a touch. The 3rd shift usually will hang out a bit more anyway. it will actually ET a bit better that way too.
What shift kit is in it? Is it a 904 by chance?

My toys get the manual valve body treatment, like 'forphorty' said. If I want creature comfort, I get in my Ram R/T.
 
It's a 727. Shift kit, if there is one, is unknown. I haven't done anything but maintenance to the transmission since I have owned it (1.25 years).

I've got the cable to the point that even the slightest tightening will shoot the shift to 3rd WAY too high.
 
it's as far as you can go then..
To get more, you'll have to install a Transgo TF-2 shift kit and use one of the supplied TV springs.
Unless, of coarse, your TV valve bore is wore-out. In which case, you'll have to use the Transgo TF-TV kit to supplement the TF-2 kit.
 
7milesout said:
It's a 727. Shift kit, if there is one, is unknown. I haven't done anything but maintenance to the transmission since I have owned it (1.25 years).

I've got the cable to the point that even the slightest tightening will shoot the shift to 3rd WAY too high.
Click to expand...

Then you need to tighten up on the 1-2 shift control valve spring, or the 1-2 shift spring so it resists the shift a bit longer.
OR order a new outer governor weight.
OR
The governor weights are basicly 3 pieces, an outer weight, an inner weight, and a spring. you can lighten up the weights and use litlle stiffer spring to raise the shift points. I believe the outer weight and spring control the 1-2 shift and the inner weight controls the 2-3 shift. There were even aluminum weights available. If you have access to a lathe you can lighten up your weights. The outer weight gets cut in the middle of the OD leaving it looking like a spool. The inner you can counter bore on the small end to lighten it.

Obviously most of this is trial and error until you get what you want, but I have always heard A&A transmission parts online gets damn close going by the description you give them.
 
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