big dave

My options were pretty limited because of the obd1/high stall curse. Either I had to switch to an obd2 computer or switch to a 700r4 tranny. I went the tranny route. Problem is, now I can't get the tranny to shift under full throttle. I've changed the govenor 3 times and played with the detent cable. Is there something else I can do or is there something else I'm missing?

LJ93Z28GM

That is about all you can change to alter the shift points.

I will go over this for you. Most tell people how to do it wrong.

Adjusting the TV cable. Push in the detent spring and pull the cable back the whole way. Have someone or yourself press the pedal in the car all the way in. Push hard you should here it ratchet the cable forward. some do it by using the throttle body but if you notice on alot of cars the pedal does not pull back as far as you can manually at the TB.

As for the governor. What are your shift points? Every trans is a little different in terms of the governor. Setup your springs so that your 1-2 shift is at the same rpm as your 2-3 shift. once you get the correct spring tension so that they are close leave them alone. Now you alter the wieghts to get the trans to shift at your desired rpm based on your HP curve.

you state the trans is not shifting at all under WOT. It could be low on fluid. It could have weights and springs that are too light and making it shift beyond your rev limiter.


What is the trans doing exactly when you do WOT. Just hitting the rev limiter or is it doing something else.

big dave

Thanks alot for the reply. I was under the impression the weights are located on the govenor so they are one and the same. If not please let me know. I didn't describe the symptom completely accurately. I'm sorry. The car does shift on the 1-2 shift but not on the 2-3 under WOT. The 1-2 shift occurrs at around 6k, around 200 shy of optimum, but at 6400 I had to lift off the gas to get it to shift. The fluid level is fine.

ltwonz

My 700r4 was doing the same thing not wanting shift 2-3. I was told by a couple of companies to let the tv cable out a couple of clicks and that solved my problem.

LJ93Z28GM

You can just back the TV cable out to make it shift but it is not the correct in terms of adjustment. Being one or two clicks off is fine but not too much more.

The problem you are seeing that your springs are not correct. They are causing the car to shift differently on your shifts. A tad early on your 1/2 and late on your 2/3.

You can play with the spring by cutting them or by getting different ones. lighter or stronger. There are a few companies that sell adjustment kits.

Yes the weights and springs are both on the governor. Obviously you can see the springs, the weights are what the springs are pushing on. You can grind away at them to make your shifts later.

This reason alone is why i like electronic trannies since they are easier to tune if you have access to the goods, but if you are a home mechanic at least you can work on a 700's shift point yourself, it just gets old fine tuning it.

If I were you I would try to back out the TV cable a click maybe two and see if it allows for the 2/3 shift just to make sure everything in the trans is wokring properly. If you are content with having your shifts not exactly were they need to be then you can leave it that way if it shifts.

I myself always shift the car manually if I am trying to race the car. Around town driving mine is about 200 shy on all shifts

psychocabbage

I used to be a 4L60e owner.. I went through 6 of them in 3 years.. No lie.
After I got rid of my LT1 I met a guy I wished I had met earlier.. He has a t400 in his Fbod. While a manual valve body may be a pain sometimes, it would be better to have than a tranny that died all the time.

I say get a T400 at the least get a T350. It has been done so if its not easy at least you may only have to do it one time and it will last!

Good luck... ohh by the way.. 700R4, coming from my friend who ran his 1991 Z28 to high 11's, that tranny is a pain too! haha He went through 4 stalls and a few rebuilds before giving up and selling the car.

big dave

Believe me, I really would prefer to have my 4l60e back. The problem is, on a hard launch (mid 1.6s 60') the car wouldn't shift into 2nd. I could've gone the obd2 route but alot of the guys that have obd2 are switching to obd1. As far as my current problem goes, I have adjusted the detent cable as far back as it will go, while being able to still go to full throttle, but that didn't take care of the problem. I normally pull it back a few more clicks for part throttle driving and the shifts feel nice and firm. If I put the accelerator all the way to the floor, the detent cable clicks back out where the shifts feel kinda weak.

12SCNDZ

You'll probably need a Sonnax "full throttle upshift" TV valve and sleeve in the valvebody. 700's aren't designed to upshift at full throttle. What governors have you tried? For 4th gen conversions, I usually start with a factory '93 Z28 governor. For cars with 3:23 gears, they'll work "as is". If the car has steeper gears, I usually have to go lighter on one of the springs.

The TV adjustment procedure listed already is correct. But even after it's set that way, you may still have to fine tune it. Most Tuned Port 3rg gens and '93 LT1 cars with 700's will also benefit from a Sonnax "TV Corrector", which keeps the cable from pulling out of adjustment when it's adjusted to achieve ideal shift points.

Frank
Cahall Performance Transmissions

LJ93Z28GM

Trying to make the car shift harder by means of the TV cable is not going to solve much. you might possibly need some different springs and valvebody work to get it to shift harder, meaning a shift kit adjusted to your likings.

Work on the governor as stated. It takes time but once you get it correct you will be all good.

Do not get a TH400 or TH350 if it is a car that you drive all the time. Currently my car will go mid twelves all day long and my current trans has lasted over 10K with no problems. It is just setting it up correctly. Had 5 other trans in there before by a different guy and they all blew up. Current one has stock soft parts with a few upgraded hard parts, nothing special.

wes95_z28

i have that conversion done on my 95 z and mine shifts at 4000 rpm at wot unless i shift it manually the kickdown cable is just somthin you gotta play with

12SCNDZ

I ALWAYS manually shift my car when at the track.

Frank

LJ93Z28GM

12secZ. The 700 is not designed to upshift at WOT on the 3-4 shift all others it will. There is a part to replace that to allow that.

wes95_z28 your car needs to have the governor altered so that you do not have to shift it manually all the time. The TV cable is just for fine tuning.

Here is parts for the 700R4 if you want to know what is out there for the trans.

transmissionhead.com

big dave

I did have a govenor for the 3.23 geared car. I was told that that was my problem and I was given the govenor that was supposed to correct that problem. It didn't. Problem is, I can't even manually shift the tranny. It does the same thing as it would with the shifter in drive. The 1-2 shift is ok at 6k but it just wouldn't shift into 3rd until I lifted at 6400. Does the govenor control both shifts?

12SCNDZ

Yes, the governor controls all upshifts. You really need to try the Sonnax "full throttle upshift" sleeve and valve. You also may be seeing signs of the 3-4 clutches slipping.

Did you install a shift kit of any kind? If you did a "Trans-Stop", you've probably fried the 3-4 clutches.

Frank

LJ93Z28GM

If you shift it manually you should be able to rev it to whatever you want and then shift it. The governor has no control over that.

The full up shift valve might not help in this situtation since it is for the 3/4 up shift. GM did not want up shift on 3/4 since the plates get heated to fast on a WOT upshift and then they are fried. How often are you really going to shift from 3-4 at WOT. You will get going over 100mph and you want a WOT upshift.

I would rather have my tranny last. As he stated above you might have already started getting symtoms of weak 3/4 clutches.

Look at the website as I said. Scroll down a long time and you will see the upshift valve and whatever else you think might cure your problems or meet your needs.

www.transmissionhead.com