Got a 727 question

[69 Runner]

Ok. My Duster supposedly has a store bought from Mancini 727 in it with some B&M floor shifter. Problem is (if left to it's own) it will NOT shift above 4500 RPM. By that I mean it hits 4500 an we're on to the next gear. It's my understanding this has something to do with a servo?

I've done a ton on these cars in the 37 years I've been workin on MOPARS, but I've never worked on a 727 (except to pull one, have it built, and put it back)

SO...what's the deal with this? Is it something that is easily changed? Hammer? Match? (btw, it has a LOKAR cable on it, and adjustment isn't the problem)

whut?:edgy:

 

[dartguy340]

Need some info here....is it a reverse pattern valve body? Do you know if it is suppose to be fully manual or not? I don't understand what you are expecting it to do when you are leaving it in drive(if left to its own). Unless the governor was left out/disabled the trans is going to have to shift at some point unless you keep it in "low" or "second".. Most of these transmissions, if set up for "RACE" were made to be shifted manually. Tell me more if you can, steve

 

[Meep-Meep]

What is your throttle pressure linkage doing? This is VITAL on a TF - unless it's some manual shift setup.

 

[69 Runner]

It has a normal pattern valve body in it, and is not a full manual. The kick down cable is adjusted to the point of almost being to tight (not allowing a shift unless you let up on the pedal). The shifter does NOT go in to the 2 or 1 position. What bugs me about this is my 69 be (for instance) which had the numbers 727 and original valve body (with B&M shift improver) would go well beyond 4500 when left in drive and the loud pedal mashed. This trans does NOT do that however. When at WOT it will only go to 4500, then shift. It should go beyond that.

 

[dartguy340]

OK, first I have had cars come to me with a Lokar cable on it and depending how it was attached to the carb it seemed like the cable "bottomed out" before the kickdown was at it's furthest point. Check to see if it is indeed pushing the kickdown lever as far as it will go, which in turn is pushing the valve in the valve body....will have to drop the pan to see it. Otherwise it may be that someone has been into the valve body and either put the valve in wrong or modified it... good luck

 

[69 Runner]

This trans was supposedly store bought from Mancini. I don't know that for a fact. The Lokar cable is definitely moving the kickdown lever, because as I stated above, if I take any more adjustment out it will make the trans hold in gear...even during part throttle operation, and will stay there until lifting on the throttle to let pressure off the kickdown. And even when I had the cable adjusted to that "hang" point, the trans would still shift at 4500. No higher.

While I've never built a 727 I think I have a grasp of how to adjust this kickdown cable. This one isn't my first.

Thanks for your response, but I don't think you've grasped the issue at hand.

 

[1badstroker]

Did you give any thought to calling Mancini and ask them since it is there trans. They might have a good quick answer for you. Your turn!!

 

[69 Runner]

Nope. Cause I didn't buy it. The P.O. said he bought it from Mancini. While in the air, I looked for any kind of identifying marks or stickers and didn't find any

 

[Meep-Meep]

It sounds like the throttle pressure (kick down) is working so maybe the governor pressure is over riding it and causing the undesirable shift point - until the TP lever is pinned. I believe the trans shifts only when the gov pressure overrides the TP, so those two are always in some kind of balance.

Something easy is to try swapping the valve body, or remove the tailshaft and check/change the gov weights. Also check the line pressure adjustment screw. Some people like to run it in all the way so the tranny feels like it will split in half with every shift.

 

[69 Runner]

Hummmmm.......well....it sounds like something I'll just have looked at whenever (if ever) I get the motor and trans out for the engine bay repaint. Phoenix Transmissions is down here, so I guess I'll just take it to them. I know I'll get exactly what I want when I get it back from them

 

[RT/10]

Very few torqueflites revved higher than 4500 rpm before shifting when left in drive. It's because the governor is the control unit that tells it when to shift and even if the throttle pressure linkage is set to full at WOT the governor will over ride it. To make it rev higher you'll need to install a higher rpm governor spring/valve package. I think you can still get them that go all the way up to 6500 rpm.

 

[69 Runner]

Interesting. You would think that IF this trans really did come directly from Mancini as the P.O. said, it would have been built for action rather than a Sunday drive (and I don't mean on the 1320) lol

 

[daredevil]

im with you Buck ,Mancini doesnt neccesarily mean performance

 

[69 Runner]

Ok...so let's assume that's the deal. How big of a job is it to swap that over?

 

[Patrick]

I had this one time with a 69 Super Bee. The transmission was in the car when I bought it and the guy had put a B&M shift kit in it. The box and instructions happened to be in the trunk. After about three months of trying to figure it out I read the old shift kit instructions. 71 and up transmissions have to have a hole drilled in the valve body. 70 back don't need this hole. My transmission was the matching 69 727 for the car. I droped the valve body and found the guy had drilled it. I got me another one from the junk yard from a 68 Charger. Put the kit in it and never had another problem. Also the shift linkage itself must be right on a 727 for it to work right.

 

[daredevil]

is the accumulator spring still in it? I think its what its called. When you install a manual valve body youre supposed to scrap that 1 1/2 spring for it to work properly.

 

[RT/10]

Change the Governor; Basically drop the drive shaft, remove the tranny mount, remove the bolts that hold the rear extention to the main case of the tranny. Under the tranny mount, you'll see a plate with two screws holding it in place. Remove the screws and plate. There's a large metal snap ring that holds the rear housing in place, spread it, tap the housing, and slide the rear housing off. You may have to manipulate the rod going to the parking pawl. Once you have the housing off, it's just a case of removing a couple of snap rings, c-clips to change the weights in the governor. The one's you'll want will look a LOT like a very skinny thread spool. To replace it, it's just the reverse of the above, paying close attention to the parking pawl rod, that's probably the most difficult part of the whole job.

If you don't have a source for the governor weights, check with Level 10, among others. I just like Level 10, when I used one of their kits years and years ago, I had the best tranny I had ever put together. http://www.levelten.com/index.html

While you have it apart, just to be safe, go ahead and check the rear bushing where the drive shaft yoke rides. Not that it has anything to do with this, but it's better to do it now if it's worn, than to repeat this whole proceedure.

Right on the money. I'll just ad that it's about a 2-3 hour job depending on your garage facilities. Also if you jack it up about 6" higher in the rear the fluid that accumulates in the tail housing will run forward and save making a big mess.

 

[dartguy340]

Very few torqueflites revved higher than 4500 rpm before shifting when left in drive. It's because the governor is the control unit that tells it when to shift and even if the throttle pressure linkage is set to full at WOT the governor will over ride it. To make it rev higher you'll need to install a higher rpm governor spring/valve package. I think you can still get them that go all the way up to 6500 rpm.

This is basically the same thing I mentioned on 3-06-09, I think you would need to use heavier springs in the governor.:yes:

 

[69 Runner]

Thanks all. That's exactly the kind of info I needed. This really bugs me now while I'm driving it, but since I 1) want to pull the motor and trans to un-Chevize the engine compartment and 2) replace the mild 360 with a less mild 408 I guess I'll wait till it's all apart and scattered all over the shop. As far as garage facilities go, I keep trying to get more. Bought a 9000# 2 post and a 7000# 4 post lift a couple years ago, and keep acquiring more stuff to make life a little easier.

Thanks again