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Rebuilt 700r4 problem.

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Old 11-26-2015, 12:47 AM
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rsc337
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Default Rebuilt 700r4 problem.

So I had my 700r4 rebuilt after loosing reverse. It was done by a reputable shop and I had it built up to handle more horsepower which I will be building up later.
The problem is that if I drive in "D"=3rd it shifts at 4300rpm at WOT from a stop and way to early. The TV cable is let loose as far as it will go. When I manually shift it, it will go to redline/rev limiter then I will shift manually with no problem.
I've got the TV cable as loose as it will go. Before rebuild everything worked great.
Any help would be greatly appreciated.
Old 11-26-2015, 01:20 AM
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Cliff Harris
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You don't want the TV cable "as loose as it will go". It should be adjusted PROPERLY to get the correct line pressure in the trans as you mash on the gas pedal. If the pressure is too low under load you will destroy your clutches.
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Old 11-26-2015, 01:57 AM
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toobroketoretire
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The TV cable should be JUST tight at wide open throttle to get the correct line pressure. Tighter will give later upshifts and looser will give earlier upshifts.
Old 11-26-2015, 08:37 AM
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PAINTER MAN
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To raise the shift point you will need to change the weights in the transmission governor. I have done this on mine. It is a bit of trail and error process. The transmission shop can do it for you.
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Old 11-26-2015, 09:44 AM
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BOOT77
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They might of mixed up your governor or it wasn't working properly before n now it is. Had mine out about 7 times when I was retuning the shift points, all set ups will vary a bit. I used a B&M governor recalibration kit, but there is a cheaper brand kit on ebay(I know because I messed up one of my weights). Springs and weights make their own changes, but the one thing I couldn't find in my searches that I learned was two stiff springs will make the 1-2 shift happen before the 2-3 shift rpm. The rest is in the directions and it's just mixing n matching to get what you want.

FYI you can grind or drill weights, but do it only a little at a time or you'll be buying another kit. Springs are mass too! Grease your cap/seal to make it come off easier for changes and after you install it a few times make sure you remove any dents from tapping it on(my 5th time the cap center was pushed in and hit the governor). I used a mirror to make sure the cap was even on the top and stole a retaining clip from a th350(not really needed just makes me feel better).

Last edited by BOOT77; 11-26-2015 at 09:51 AM.
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Old 11-26-2015, 11:12 AM
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rsc337
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Happy Thanksgiving to all! Thanks everyone for all the info because I'm not a tranny guy and I'm learning as much as I can on this. My car is a 92 and it has a spring loaded TV Cable that is opened or closed by a clip. The early shift point is only from 1-2 shift. The 2-3 shift point is good. The trans guy said he will fix it no problem but I cant take it back until next Friday. Thanks again for all your help.
Old 11-26-2015, 11:21 AM
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Originally Posted by rsc337
Happy Thanksgiving to all! Thanks everyone for all the info because I'm not a tranny guy and I'm learning as much as I can on this. My car is a 92 and it has a spring loaded TV Cable that is opened or closed by a clip. The early shift point is only from 1-2 shift. The 2-3 shift point is good. The trans guy said he will fix it no problem but I cant take it back until next Friday. Thanks again for all your help.
Your '92 has ASR and the TV adjustment is dramatically different than just conventional 700R4. If the shop doesn't understand you need to either learn yourself or make the shop aware of the fact the car has ASR UNLESS of course something has been done to defeat the ASR OR ???

There's a few good threads here covering ASR/TV look for threads by maybe "toptechx6".

Last edited by WVZR-1; 11-26-2015 at 11:24 AM.
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Old 11-26-2015, 01:43 PM
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Thanks wvzr-1, Your right and there are different adjustments around the ASR. I will search the other threads also. Thanks.
Old 11-26-2015, 11:06 PM
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rsc337
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I'm curious as to what other people with a 92/3 are going to,in RPM, in shift points at 1st-2nd shifts, In drive/3rd gear at WOT? Not OD.
Old 11-27-2015, 07:33 PM
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The shop needs to fix it, hopefully they'll stand by their work. It sounds more like a governor issue, than a TV issue but I could be wrong.

Hopefully they're familiar with 700r4s in Corvettes, and specifically 92s & 93s. My 93 is same as yours, ASR integrated with throttle & TV. Years ago a shop fixed a pump seal in my trans & used the "regular" method of setting the TV cable for a 700r4, which messed it up. It never worked right until I fixed it, after doing the TV cable method in the FSM. Luckily they had it too tight, too loose can cause line pressures too low, & damage the transmission.

The only precise way to set the TV cable on a 92 or 93 is to use the method in the FSM, & ideally verify all pressures are in spec.
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Old 12-03-2015, 11:19 PM
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Ok guys update. I got a FSM and adjusted the ASR to factory specs but when I did that it broke part of the ASR and I was following the FSR to the letter! I don't believe the 71lbs. of torque the FSM states! The ASR is Aluminum and it broke. The ASR is still working correctly but now I've adjusted everything manually. I took the car to my Trans guy and explained it and whats going on and now it shifts great after he modified the Govenor. The key item was the Govenor and weights and springs for major shift point changes.
Old 12-03-2015, 11:37 PM
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71 inch lbs perhaps?
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Old 12-04-2015, 12:46 AM
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Thanks Cuisinartvette. You were right and I over torqued it and broke it. It still works. Lesson learned.

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