Need help My TH 400 behaves just fine on the street, but I get no 2-3 shift at full throtle on the track. Either in Drive or shifting manually. No slippage noted. Full throtle 1-2 shift in Drive occurs at about 4400, governor is out of a 74 Electra trans and has not been modified. Rest of the trans is supposed to be out of a late 70s Chevy truck. (Not sure how a late 70s Chevy truck had a BOP case???) Trans was apart back in the Spring at Mike Kurtz's shop for an intermediate sprag, but they said every else thing internal (clutches and bands) looked fine.
Is it possible for you to install another governor and see what happens? First thing I would look at is the governor. Maybe one of your weights isn't coming out like it should. I would take it out and look at it very carefully. Make sure nothing is stuck or missing. John.
Nick, Also, is it possible the trans is in 2 and not in drive? Maybe the linkage? Check the governor, make sure it isn't gummed up. Also, check the detent solenoid. If it sticks open, it could cause a problem like that.
Based on the troubleshooting in the service manual I'm thinking detent solonoid. Is that a parts store part? I could try one from a spare tranny, but, not a job I want to do twice. Definitely is going into third just fine in regular driving, so not a linkage/adjustment problem. I can watch the shifts on the tach, and just drove several hundred miles to Temple--would have know if I were in 2nd on the highway!! :grin: I "think" I have another governor to try. Need to check the spare trannys. The big problem is diagnosing whether I have fixed the problem. Since I live "In the big city" the only way to get a full throttle 2-3 shift costs $20 at the track.
I would try the governor first. You may have lost a spring. Take the car on a highway and nail it at 60MPH. See where it goes back into 3rd. That is the way I tested my WOT 2-3 shift when modifying my governor. The downshift solenoid is not a parts store item, go to a trans shop.
Resurecting an old thread for an update... FINALLY got around to pulling the governor. The swagged joint between the stamped steel head that holds the weights and the machined steel valve was loose, effectively preventing the weights from ever moving the piston in the valve. Put in a new governor, with 70 GS 455 weights installed. Going to the track tomorrow; very hopeful that all is well :3gears:
2-3 shift just picked my car up today from the trans guy, this is the 3rd time its been back since he rebuilt it.the 1st 2 times he cut back the accumulator spring and the car would shift 3rd when i let off the gas,this only happened at the track at wot.today he said he cut another half link off the spring,changed the gov and put a new stall in just for peace of mind(3800 stall). this guy tells me today that he thinks the stall may be to high for my set up,car runs low 12s,has anyone ever heard of such a thing, or is this guy just totally out of line? the guys been in bus for 20 years,also forgot to mention i have switched gov before and same result.any comments appreciated thanx.
I don't understand what you mean here? Shifts to 3rd when you let off the gas? It's is supposed to do that. And what are you doing letting off the gas at the track! LOL :shock: :3gears: Are you happy with your WOT shift points in Drive? If so, you are changing the shift point each time the governor is changed, unless he is swapping the weights and springs. 3800 sounds like way too much stall for a 12-sec car.
2-3shift I am not happy at all with my shift points, the rpms were up to 6000 grand and i was not in 3rd gear yet.What i mean by letting off the gas is,weather it is man or auto shift the acr will not hit 3rd unless I let off and then get back into it.The 1st time Ihad to release the pedal all the way up,now I just lift a little and it will shift.This is why it is believed that the spring is to tight and by letting off the gas , it is releiving the spring pressure,allowing it to shift.Could you please explain why a stall that is to high would not allow the trans to shift? Im kind of new to this and am just looking for some answers.Thanks again,I welcome all comments and help,just wanna go faster. :3gears: :3gears:
How does the trans shift otherwise? During normal driving? Is the kickdown hooked up? Is it operational? Have you tried changing the governor weights and springs?
2-3 shift The trans is fine on the street,not sure about the kickdown,and i have changed the gov,weights,and springs twice with the same results.
In order for the trans to shift correctly, everything has to be hooked up and operational. The vacuum modulator must be good (diaphram leak free, full manifold vacuum and no restrictions in the supply line). The kickdown must be hooked up, and working. The governor weights should be changed one at a time, the car roadtested, and the change evaluated. The B&M kit makes this easy to do. Trial and error, time consuming, but well worth it. First make sure everything is hooked up correctly. If not, you're not going to get anywhere.
The converter has absolutely nothing to do with the shift points. You are simply giving away the torque that your motor makes below 3800rpm with that high of a converter. My guess is that the weights on your governor are way too light. IMHO, this tranny guy is not the right guy to be working on your car. First off, I can't imagine why he would put a 3800 stall converter behind a street driven big block Buick. Second, I suspect he is thinking in SBC world and is setting up your governor to shift at a billion RPM.
2-3 shift convertor been away awhile, computer down.just wondering why a 3800 stall would be to high and what would you recomend?car lost 2 tenths in 60 ft with changes.
Well, it all really depends on the combination in your motor. But if your motor is making just as much torque at 3500 as at 3800, then there is no advantage to a 3800 stall converter. With a 3800 stall you will always be slipping the converter during normal driving, which generates a lot of heat (a transmission's worst enemy)
