727 Line Pressure VB + Light Governor

threewood

Well-Known Member
Local time
12:42 AM
Joined
May 30, 2014
Messages
5,339
Reaction score
7,115
Location
Artesia, NM
Going to pull the tail housing to swap my governor out to stock governor.

Currently have an auto shift VB from Cope and a 5600rpm governor. 727 rebuilt with billet parts.

Issue...will not up shift in auto, and sometimes manual unless I let up a bit.

Bouchillon cable operated throttle pressure. Yes it is adjusted correctly. Yes it has the correct throw arm.

VB is auto shift, guessing same mods as Transgo 727 shift kit. Higher line pressures included. This, in conjunction with a lighter governor is what I believe to be the issue. Too much pressure upping the shift point beyond what it should be.

I'm going to swap back to a factory governor and see if it lowers the shift point.

Thoughts?
 

Wietse

Well-Known Member
Local time
9:42 AM
Joined
Apr 16, 2017
Messages
1,890
Reaction score
817
Location
Netherlands
Did you check actual line pressure on the test port? (middle one on passenger side)
Transgo kit should have around 95 psi line pressure, in D with the brakes applied and min. 1000 rpm. (hot oil)
This is with the throttle lever at the transmission fully pulled forward. (disconnect lever and use a zip tie or something to keep it fully forward)
You could try and reduce pressure by backing off the regulator adjuster, depends what pressure you find.
 

dvw

FBBO Gold Member
FBBO Gold Member
Local time
3:42 AM
Joined
Feb 16, 2010
Messages
6,495
Reaction score
9,878
Location
waterford mi
Why not talk to John Cope? He built the valve body and know what it takes.
Doug
 

threewood

Well-Known Member
Local time
12:42 AM
Joined
May 30, 2014
Messages
5,339
Reaction score
7,115
Location
Artesia, NM
Why not talk to John Cope? He built the valve body and know what it takes.
Doug
I emailed and haven't heard back. The different time zones and work hours don't mesh.
 

EngineerDoug

Well-Known Member
Local time
12:42 AM
Joined
Oct 5, 2016
Messages
292
Reaction score
141
Location
Los Gatos, CA
Threewood,

I am having a similar issue with my 727. Completely rebuilt by me...my first automatic transmission. I kept everything surgically clean and followed instructions to the letter. Used top quality parts and one of CRTs Street valve bodies. My transmission a 400 big block version circa 1974. Stock governor. I am also using the Bouchillon cable kit.

I found that my 1-2 shift was too early, and the 2-3 shift was too late. Adjusting the throttle linkage for more throttle pressure, and it would not shift from 2nd to 3rd even at steady speed ~40mph. Adjusting the linkage for less pressure and the 1-2 shift happened at maybe 5mph. We're talking light throttle operation here, BTW.

I contacted John at CRT and he indicated that I could return the valve body for a replacement...but the gist of the conversation was that I needed to fine tune the throttle cable adjustment.

I played with the adjustment a bit more and arrived at a compromise setting that gives a later 1-2 shift, but will still shift from 2-3. Sometimes I have to let off the throttle just a bit to get the 2-3 shift. Small changes at the cable made a big difference.

Now I am not even close to a Torqueflite expert, and I am fully aware that John at CRT is one of the best in the business. So I have a hard time believing there is anything wrong with the valvebody. It is also very interesting to hear I am not the only one who is experiencing this sort of shift behavior.

Could it be that the stock governor is so mismatched with the rest of the transmission hydraulics? I will be interested to hear it goes as you investigate this issue.
 

threewood

Well-Known Member
Local time
12:42 AM
Joined
May 30, 2014
Messages
5,339
Reaction score
7,115
Location
Artesia, NM
Threewood,

I am having a similar issue with my 727. Completely rebuilt by me...my first automatic transmission. I kept everything surgically clean and followed instructions to the letter. Used top quality parts and one of CRTs Street valve bodies. My transmission a 400 big block version circa 1974. Stock governor. I am also using the Bouchillon cable kit.

I found that my 1-2 shift was too early, and the 2-3 shift was too late. Adjusting the throttle linkage for more throttle pressure, and it would not shift from 2nd to 3rd even at steady speed ~40mph. Adjusting the linkage for less pressure and the 1-2 shift happened at maybe 5mph. We're talking light throttle operation here, BTW.

I contacted John at CRT and he indicated that I could return the valve body for a replacement...but the gist of the conversation was that I needed to fine tune the throttle cable adjustment.

I played with the adjustment a bit more and arrived at a compromise setting that gives a later 1-2 shift, but will still shift from 2-3. Sometimes I have to let off the throttle just a bit to get the 2-3 shift. Small changes at the cable made a big difference.

Now I am not even close to a Torqueflite expert, and I am fully aware that John at CRT is one of the best in the business. So I have a hard time believing there is anything wrong with the valvebody. It is also very interesting to hear I am not the only one who is experiencing this sort of shift behavior.

Could it be that the stock governor is so mismatched with the rest of the transmission hydraulics? I will be interested to hear it goes as you investigate this issue.
I've played with cable till I was blue in the face. Get it to upshift where it should then it wouldn't downshift to 1 at a stop. Right now it is upshifting and downshifting while driving normal. It only hangs up at wot. If I stay into it it will eventually shift but well north of 5800rpm
 

BSB67

Well-Known Member
Local time
3:42 AM
Joined
Jan 18, 2018
Messages
1,989
Reaction score
1,704
Location
PA
T

I found that my 1-2 shift was too early, and the 2-3 shift was too late. Adjusting the throttle linkage for more throttle pressure, and it would not shift from 2nd to 3rd even at steady speed ~40mph. Adjusting the linkage for less pressure and the 1-2 shift happened at maybe 5mph. We're talking light throttle operation here, BTW.

I contacted John at CRT and he indicated that I could return the valve body for a replacement...but the gist of the conversation was that I needed to fine tune the throttle cable adjustment.

I played with the adjustment a bit more and arrived at a compromise setting that gives a later 1-2 shift, but will still shift from 2-3. Sometimes I have to let off the throttle just a bit to get the 2-3 shift. Small changes at the cable made a big difference.

Now I am not even close to a Torqueflite expert, and I am fully aware that John at CRT is one of the best in the business. So I have a hard time believing there is anything wrong with the valvebody. It is also very interesting to hear I am not the only one who is experiencing this sort of shift behavior.

Could it be that the stock governor is so mismatched with the rest of the transmission hydraulics? I will be interested to hear it goes as you investigate this issue.
Get the 2-3 to shift where you want (governor/throttle adj.), then adjust the 1-2 shift valve spring. It will need to be a little stiffer spring than the one that is in there now. This is easier than getting the 1-2 to shift where you want and finding a softer spring for the 2-3 shift valve.
 
Last edited:

BSB67

Well-Known Member
Local time
3:42 AM
Joined
Jan 18, 2018
Messages
1,989
Reaction score
1,704
Location
PA
Going to pull the tail housing to swap my governor out to stock governor.

Currently have an auto shift VB from Cope and a 5600rpm governor. 727 rebuilt with billet parts.

Issue...will not up shift in auto, and sometimes manual unless I let up a bit.

Bouchillon cable operated throttle pressure. Yes it is adjusted correctly. Yes it has the correct throw arm.

VB is auto shift, guessing same mods as Transgo 727 shift kit. Higher line pressures included. This, in conjunction with a lighter governor is what I believe to be the issue. Too much pressure upping the shift point beyond what it should be.

I'm going to swap back to a factory governor and see if it lowers the shift point.

Thoughts?
Weigh the inner weight of the original, and the 5600 governor. Then you can pretty much nail the correct rpm shift point by removing some weight from the original, if the original shifts too early.
 
Last edited:

threewood

Well-Known Member
Local time
12:42 AM
Joined
May 30, 2014
Messages
5,339
Reaction score
7,115
Location
Artesia, NM
FTRI (failure to read instructions)
#5 says to not modify governor. I already had the tailshaft pulled so I swapped in the stock governor. I'll get it together tomorrow for a road test.
20220805_213916.jpg
 

threewood

Well-Known Member
Local time
12:42 AM
Joined
May 30, 2014
Messages
5,339
Reaction score
7,115
Location
Artesia, NM
Weigh the inner weight of the original, and the 5600 governor. Then you can pretty much nail the correct rpm shift point by removing some weight from the original, if the original shifts too early.

I don't have a scale to weigh anything that little. Original was full size, lighter spring. The 5600 was drilled out and the cap thinned with a heavy spring. I did drill out the center weight of my stocker a bit, not too much. I figure the pressure increase of the vb would bring the shift point up enough on its own.
 

74gtx

Well-Known Member
Local time
3:42 AM
Joined
Mar 25, 2016
Messages
151
Reaction score
107
Location
Ohio
Hi threewood, any luck yet? I have a similar issue.
thanks, Mike
 

74gtx

Well-Known Member
Local time
3:42 AM
Joined
Mar 25, 2016
Messages
151
Reaction score
107
Location
Ohio
I have no idea what governor I have but my engine starts to float the valves and pop through the intake if I don’t get out of the gas pedal. I’ll try to find a stock one and see if it works. I’ve tried every adjustment possible on the kick down with no luck. Was it hard to do the governor?
 

threewood

Well-Known Member
Local time
12:42 AM
Joined
May 30, 2014
Messages
5,339
Reaction score
7,115
Location
Artesia, NM
I have no idea what governor I have but my engine starts to float the valves and pop through the intake if I don’t get out of the gas pedal. I’ll try to find a stock one and see if it works. I’ve tried every adjustment possible on the kick down with no luck. Was it hard to do the governor?
Not hard but takes a while to get to. Do you have a modified VB?

I had to drop the exhaust w/ cross member, drop drive shaft, drop trans mount, lower tail housing far enough to reach top bolt, expand the retaining clip, pull housing back enough to see governor.
 

74gtx

Well-Known Member
Local time
3:42 AM
Joined
Mar 25, 2016
Messages
151
Reaction score
107
Location
Ohio
I’m not sure what’s considered modified but I did install the tf2 kit in hopes of it helping. I think it was already messed with though.
 

Wietse

Well-Known Member
Local time
9:42 AM
Joined
Apr 16, 2017
Messages
1,890
Reaction score
817
Location
Netherlands
The TF-2 kit is intended to use on a stock transmission, using a modified governor will not be "fixed" by the kit.
If the valve body has been modified it can go in all directions, i also found out (afterwards) my valve body is actually from an earlier year 727 and had a B&M kit installed and is (still) giving me a ton of issues i am still sorting out.
Checking pressures is a must to get it right.
You can test your governor pressure with a test gauge and a micro bore hose, the pressure should match the road speed in psi and should come up as soon as you start to drive. (i.e. 10mph=10 psi, 50mph= 50 psi)
When coming to a full stop, the pressure should come back to "0".

If the car has the original governor but the tire size and/or rear end ratio has changed, things will be off and it will not shift at the right times. (i.e. my car governor pressure starts at 15mph and is too high already at this point, it shifts too early)
Shift points are a simple balancing act between your throttle pressure (engine power) and governor pressure (road speed) and are the only 2 inputs the transmission can rely on to act (shift) as required.

If the governor pressure works as described above, you need to adjust the throttle linkage.
Basically the throttle lever on the transmission has a point where it will start to increase the line pressure and a point it provides max. pressure. Note that these points are not at the start and end of the lever stroke, specially the TF-2 it will be different as they tell you to grind down the short throttle valve spool for this.
These 2 points need to match your throttle pedal idle and WOT position.
This ensures the trans gets a 100% clear signal of what you are asking for.

To get this set is a bit difficult, you will need to have the car raised off the floor for safety reasons, with the transmission in D and the brakes applied to avoid wheel rotation and the engine running at min. 1200 rpm (this to ensure the trans oil pump is delivering sufficient flow) with the transmission at operating temperature. Record the Line pressure it gives.
In this condition you need to adjust the throttle linkage so, that whenever the pedal is slightly depressed, the line pressure starts to increase straight away and reaches max. pressure at the WOT position.
(again, with the TF-2 kit i also found around a 1/4" stroke lenght of the throttle lever at the trans was still left, but the pressure did not increase during that section)
When you start playing with the 2 linkage adjustments, note down to changes you make and record the pressures, you will figure out quite fast what adjustment changes which point in the line pressure and continue adjusting it till it is right.
For checking the WOT position: make a reference point of where the upper linkage is at when at WOT so you you can remove the linkage from the carb and push it manually to that position and verify max. pressure is at that point. (or it is before or after that point, which means it needs adjustments.
If you made changes, you need to switch the car off, push the pedal to the metal and redo the reference point at WOT as it had changed after you made adjustments and verify your pressures again at the above circumstances and manually operating the throttle linkage.


And even after all this it could still shift at the wrong points, then you need to start playing with the 1-2 and 2-3 shift valve springs by installing a stiffer or lighter spring, depending the shifts are too early or late.
But setting the throttle and governor pressure as described above are the basics, if this is off you can play around and get it shifting where you want it, but it could still damage your transmission if there is not sufficient pressure.
This may cause slipping/burning the clutches and bands, harsh/soft shifts et.c
 

74gtx

Well-Known Member
Local time
3:42 AM
Joined
Mar 25, 2016
Messages
151
Reaction score
107
Location
Ohio
Thank you for such a great post and all of the time you put into it. When I have some time I’d like to pm you if that’s okay with you. Thanks! Mike
 

Top