904 Lockup Transmission Adjustment Help needed

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schultec14

schultec14

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Hi, I have a 904 lockup out of a 1979 grand fury had a shift kit installed and had the converter peeled open to stall at 2200 rpm, kept lockup, and I have it behind my small block in an A Body. And thats it, no other special work done. The problem I'm having is it will shift 1st, 2nd then automatically into 3rd lockup. Adjusting the kick down doesnt seem to help much, but it always wants to shift from 2nd right into 3rd lockup at 30 mph with light throttle, or any speed for that matter and with 2.76 gears and 26.5" tires, that makes the car chug. I want to adjust it so it goes into lockup at a higher speed, maybe at like 45 if possible since it has a small cam. How can I adjust when it locks up?? Id like it to shift it a little later too, but I guess I can put a little stop in front of the kickdown so it doesn't come all the way back and shift too early at light throttle... Please advise!
 
...........What shift kit, who installed it.......sounds like somethings no rite in the valve body.............kim.........
 
It was a transgo TF-2 shift kit it shifts kind of firm on its own from first to second and then it shifts firm shifting from second straight to 3rd lockup if its over 30mph...Sometimes if I do shift it manually, it will be a more firm shift, but...If i drive it easy, the earliest it will shift into 3rd is 27mph (which also seems early to me with a 2.76 rear and a 26.5" tire, so I would like to fool around with a kick-down stop, because the adjustment is maxed out...) and when the car climbs to 30mph it immediately locks up too early. That 3mph range is the only time i see it out of lockup. If I could, Id like it to kick in at 45-50 mph truthfully...that would be the best time..Even holding the kickdown down a little farther just delays the gear and not the lock up feature it seems...I know the transmission internals are good, but what should I do or look for?
Thank you,
-ANTHONY
 
..............u need to get back into that vb, somethings not rite.....get the line pressure checked, my guess is that its low......kim.......
 
Ok, what do you think it could be that would make the pressure lower? Front pump, or the valve body leaking at the mating surfaces a little?
 
......Could b the pump, if it looked worn ,it is...........how many turns is the pressure regulator set at?, what r ur bands set at?.....what is the front lever ratio?.........did u interpet the instructions rite?.......adjusted the manual valve?.............kim........
 
If it is going right to 3rd after 2nd there is a problem in the valve body as for lock up on top of third I have had to change the spring or stretch the original spring to make lock up come in later.
 
I also have a very similar setup (340--2.76 ratio--but no shift kit). I also would like a larger spread between 3d and lockup. Mine also is about 3 mph. If rdakota340 could tell the scource of a new spring or part #. Or if anyone can say how much to stretch spring that would be appreciated. Does a little make a lot of difference or do you need to stretch it right much? I have heard when people complained there was a service bulletin and different spring that could be installed for later lockup. This was a later service bulletin and not the early production bulletin.
 
..........Appears the OP fixed the problem or doesnt want/need our help anymore.....dodge may have a part# for the spring..........u may also be able to shim the spring with a washer to delay lock up..........kim..........
 
I have someone who supposedly is getting a factory spring for me that will delay lockup until about 55 Mph. If it works out that way I will post part #.
 
Have you tried lowering the line pressure?You maty have to change the spring in the lock up housing to a firmer spring to delay lock up with to higher line pressure.
 
I do have it installed now, and it did make a difference. Not as much as I had hoped, but still much better in my case. The Mopar part # is 04186185 PLT/SPRG, and the label has a printing date of 1985, and an additional code that says 8 89 that might be the actual package date. My car shifted almost immediately into lockup at the lightest acceleration. I have a 340 with Comp 268 and Edelbrock 650 in a 1968 Dart Convertible, with small 215-60-14" tires that measure approximately 23 1\2" diameter and a 2.76 ratio. The car on light acceleration now will shift to 3d and not lockup until about 39 to 40 MPH using GPS. This works out to be about 1700 rpm and then falls back to 1500 rpm. At brisk acceleration the car remains in 2d past 40mph and then it falls almost immediately into lockup again. The package contains a heavier spring, but also a new plate that has two holes drilled in it. The one I removed was solid. I wonder if drilling the holes larger would increase the lockup speed, but that would be a guessing game. My torque converter also seems to be really tight and chokes the motor down whenever shifting the motor into drive or reverse at idle. 800rpm. I don't know if that makes any difference.
 
Attempting to upload photos of Mopar parts to increase lockup speed.
 
I don't think you should have a 800 rpm engine speed drop when put into drive or reverse,sounds more like engine tune.
 
Sorry, didn't mean to mislead. Idle speed is 800 rpm to start with and it drops more than normal when the engine is put into drive or reverse. The car is also trying to pull away more than normal at idle speed. I have verified that the converter is for a lockup transmission but I know they make more than one stall
and mine is the low stall.

Also is there a link for posting pictures? I thought I had done it right, but they did not show up.
 
The low stall speed is bringing your idle speed down,a higher stall will help,but to high of a stall may give you problems with the 2:76 axle ratio.
 
Second attempt to display photo. These are the Mopar parts to delay lockup as described in an earlier thread.
 

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