I have the L98/700r4 combo--92 Formula. I've known since I bought this car the trans needed a little tweeking. It's not bad, but at the same time it doesn't seem to plant you in your seat and hit just right when you get the green light like the Formy I had a few years back. It seems to take off, then hesitate slightly, then take off again. It doesn't do this when you put it in first gear and take off, only when you're above first on the shifter. But I noticed something else. This car NEVER goes above 2000 rpm at any time as it moves up through the gear box. I don't know very much about transmissions, but that seems odd to me. You'd think you'd hit 2500 or 3000 in the low gears, esp if you nail the gas when you take off. But no, it never does. It's almost like its shifting into second a little too soon, and that's the "double clutch" (in the colloquialism sense) I feel instead of a steady application of power. So, 1. Is this normal? (Doesn't seem like it to me, my other auto trans cars hit closer to 3k or more at take off--albeit they are V6's) and 2. If it's not, is this something that can be fixed without a full rebuild? I thought the ecm controlled AT shift points? I have a new ecm, but it did this with the old one too. BTW, my rear end is a 3.23, and part of the mystery is I don't know the ratio on the Formy I had years ago. I didn't even know what a gear ratio was back then. LOL

 

Could benefit with a Corvette Servo if it dose not have one yet.


It firms up the shifts some from slipping as much and thus is actually better for the transmission = stronger shifts = less slip = less heat....


I did it myself and love the way it shifts now, of course the 3.42s don't hurt . = Corvette Servo Installation Link =


http://sethirdgen.org/servo.htm

 

You could have multiple issues.

TV cable adjustment may be a bit off. This should not be done to raise shift points per se. However, it is possible a tauter cable firms up the shifts a bit and you see a different "character" out of the car. I like to adjust it a click and drive some, making sure shifts are remaining positive and firm at part throttle, becoming quicker at greater throttle opening.

The governor could be mismatched / to the valvebody. In short, a matched VB / gov. for a WS6 model should be crisp and offer shifts on the 5000 range at WOT. A TBI truck would have a less crisp, slightly lower shifting setup. You know you bought it used and maybe the trans. codes will tell you what it 's from. A core you know is from an original G92 model or Vette would be worth a few bucks IMO for the VB.

Also, a non-highstall converter can make a trans. act poorly and keep the engine from operating in a peppier rpm range. I like the factory stuff from a G92 model or 4.3 S10 just fine. If you find your trans. is in good shape, a converter swap would be worth it. Bit just buying "any old rebuild converter" from the supply place can.be a big mistake.

 

Ok, my iPad changed ecm to exam in my op....I was saying I thought the ecm controlled shift points. Anyway, sounds like a transmission shop deal to me. Most of this sounds over my head, although I do understand a good bit of it. A rear end I might be able to rebuild, but an AT is off my scale. I'm not sure if the trans is original or not, it probably is, but I don't know what converter might be in it. It may just be worn out, the car has 156k on it. Where are the numbers that would tell me that? Are they visible with the tran on the car? Is there a vin number on it that connects it to the car? So then my original observation is valid? It's not supposed to be shifting at 2000 the way it is? I have one of the best trans shops around about .4 miles from my house. There's a guy there that's been doing it for about 45 years. Even guys from other shops in the area call him for advice. I just didn't have the cash on hand right now to get it gone through. If I ever take it to him, I'll show him some of your suggestions here, he'll be able to interpret it and say how to proceed.

 

One more question, what is a TV cable, where is it, and how do you adjust it? Forgive my ignorance, trans aren't areas I've studied much yet--been too busy working on other issues...

Update......watched a bunch of YouTube videos, and now know what a tv cable, 2-4 servo and trans governor is. LOL Thx for the tips. I may try the servo change, and I'll check my cable for tightness asap. What you said about the governor makes sense too because of the low shift points, that could be part of it, but I don't think I can do that myself.... The odd thing is, once you get it going it seems to shift smoothly, it just does it too early. Do you think changing the servo could possibly fix that?

 

Servo won't change shift timing; only how firmly it shifts, once it decides to do so.

You need a governor. Sounds like somebody put a transmission that has one out of a diesel application into your car. It's really quite easy to swap.

Definitely get the cable right first. See http://www.tvmadeez.com/article/index.php for some education. Then go here http://www.bulkpart.com/2/category/4L60-700R4.html about halfway down the page, in the "Hard Parts" section, and get the "shift point package". Might also want to consider the Transgo shift kits, near the bottom of the page; the SK-700 is the usual deal for a street driver.

While all 700s are "the same" externally (except for BH bolt pattern and extension housing), the guts that determine how they shift and all that, can be VERY different internally. Sounds like yours has been off-the-shelf swapped in a shop, where somebody just grabbed the first one they reached and slammed it in there, but it's NOWHERE NEAR right for a car of this type.

 

So do you think the governor swap is something I can do? I have very limited experience working with transmissions. I have the shop manual for the 92 Firebird, and can do all kinds of research online if I need to. If it doesn't involve pulling the tranny, I might be able to do it, and I like to learn to do it and do my own work. I've never pulled a tranny before, and I don't have a lift. So if I can make sure my cable is tight, do the servo change and do the governor change myself? I could save a few hundred and get the tranny where it needs to be.

 

Ok, so I looked at the hard parts page you suggested. I don't need to change the entire governor, just the weights attached to it? I know the weights control shift points, but I didn't know you could change the weights. Makes sense, I just never thought about it. That's why I'm on here......

Update: found some pics of the governor location. Right there at the back! Can I get that out without dropping the tran? But I think I see now. That's where the speedo drive gear is isn't it? What governor is supposed to be in a WS6? And if I get that shift point package, how am I going to know what weights to put in it?

 

You won't have to remove the trans completely; might have to remove the crossmember, and lower it a bit, though. Once you get past that, not much to it.

It's on the opposite side from the speedo gear in that trans if memory serves but memory is foggy. You know what they say; your memory is supposed to be the 2nd thing that goes away as you get older, but I forget what the 1st one is supposed to be...

"WS6" doesn't have anything to do with the governor. That's a suspension package. Your car would have come with the same governor as any other Camaro or Firebird with a V8.

The spring & weight kit will come with some sort of instructions. But just at a guess, look at what's in your transmission now, and pick a set of weights that's say 25% heavier than that. Should move the shift points up by 25%. Or, take a look at the range they send you, and pick some that are about 2/3 or 3/4 of the way from lightest to heaviest. Whichever way you go, try it and see if you like it. If it's not enough, ... put in heavier ones. If it's too much, ... put in some not so heavy. It's called "tuning".

 

Ok. It's going to take me a while to digest this. A lot of it is new, I'll have to chew on it a while. I think I get the concepts, but I'll study it out some more. You've given me some good starting points, I may be back here if I have more questions! Thx!


Wait, now more question.... I don't have a lift, so if I have to use ramps, I'm assuming I need to put a jack under the transmission when I remove the crossmember. If so, where is the best place to put the jack to safely get the job done?

 

For lowering the transmission, under any aluminum (case casting) part behind the pan. There's actually relatively little weight on it; not much more than half the weight of the trans itself, since the front half is being held up by the motor.

 

Ok, thx for all your advice.....and I've read you might have to take the distributor cap off too if you lower the trans much. Might not have to, but when I get around to this I may do it anyway just to be safe.

 

Just had a thought, wondered what any onlookers might think. After you've established the TV cable is properly set, instead of spending $50-$70 on weights and having to take the governor apart and mix/match/test and etc., wouldn't it make more sense just to get this and install it? It's brand new all around and made for Z28, Formula, Vette, etc, and it's only $65.

http://www.ebay.com/itm/700R4-7R4-700-4L60-New-Sonnax-730-Corvette-Z28-Governor-Assembly-Firebird-GTO-HD-/350443758852?pt=Motors_Car_Truck_Parts_Accessories&hash=item5198136504&vxp=mtr

 

Yup, you could try that as well...

Still might require tuning, but it might fix it right up. Hard to guess. Worth a try though.

 

There's one more thing I need to mention here. When I say the car never goes above 2000 rpm, I'm not talking about WOT. I've never tried WOT on this car because there was too much about it I didn't know, plus I DO know I need rear end work done, so I didn't want to break a gear. I've babied it a lot so far. It was just my own ignorance that most true shift points are measured at WOT. What I'm talking about is, say, like you want to race someone off a stoplight, so you nail the gas just enough for it to hook up as much as possible without getting tire spin. So then we're talking about 40-50% throttle. My other cars (V6's, one of which has a 700r4) both go from 1 to 2 in the 3000ish range, the Firebird shifts around 2000 under the above mentioned conditions, and the application of power is uneven instead of the steady increase you get from a healthy setup. Does any of this effect the situation or advice you gave me? I'm sorry I wasn't more clear, I just didn't realize at the time I wrote my OP. I'll try WOT this weekend, but I can almost guarantee its not 5000.

 

Ok, just tried the TV cable set. I followed the instructions, which say to depress the button and slide the adjuster all the way back. I did that, and then pulled the throttle back out to wto. The instructions say that's supposed to ratchet the cable into position, but it didn't. There was no change in the position, or any ratcheting that I could see. I drove the car, and it shifted too hard, which meant the cable was too tight. But how could that be when I would think pushing the adjuster back towards the trans would loosen the cable?

So I brought it back home and put it back to about where I thought it was and drove it again. It must not be exactly where it was because there is a slight improvement in the acceleration curve, the short hesitation isn't quite as bad. It shifts from 1 to 2 at around 20 mph, which is fine with me. It also would just slightly bump when it downshifted from 2 to 1 before, and I don't feel it doing that now. So the cable has something to do with it, but my adjustment was mere guessing! That can't be right, theres supposed to be a hard and fast place for it to be set isn't there? Especially with an idiot that doesn't know what he's doing? There's also another issue. I can rotate the throttle to wto with my hand, but the gas pedal itself leaves about a 3/8" gap at the throttle short of wto when you fully depress it, this may also be part of the issue, but how do you adjust THAT?

 

http://www.tvmadeez.com/article/index.php

 

Ok, I'll check that link out thx. One more thing I just noticed. The gas pedal will rotate the throttle to WTO when the TV cable is disconnected. It's the tension on the TV cable itself tht is keeping it from doing so. I guess this means the plunger is fully set before WTO is achieved. The trouble with this car is that there are just too many unknowns. I don't know it's repair history, I know virtually nothing about it and have only had it for one year myself. I'll do some more checking....

 

I've already been using this page. That's the page I used to do the adjustment I talked about before!

 

When you rotate the throttle linkage to WOT (Wide Open Throttle), the tension on the inner of the cable resulting from the link bottoming out in the transmission, is supposed to pull the cable outer through the "ratchet" just until the length of the outer matches the inner.

Might take ALOT of force on the gas pedal to make this happen. Think, like stomping on a cockroach.

Might also be a good idea to verify that the gas pedal actually moves the TB to WOT, by having your assistant depress the pedal while you observe the TB. Absolutely nothing will ever work right until the car is made capable of opening the throttle all the way. Eeeeeezy enough to bend the pedal bracket, peal link itself, cable bracket, etc. etc. to fix a failure condition in this area.

 

What you said about it taking a lot of force was helpful. I went out and went through the routine again, only this time when it wouldnt rotate to WOT I forced it. It made a snapping sound and went into position. You can tell the plunger is bottomed out at WOT now, so that's good. I test drove it, and it's slightly better than it was, but not much. My thought is I've just got an old tranny that's going to need to be gone through in a couple years when I get the cash. LOL I may just leave it alone for now, maybe do the servo change. With all this, I'm not convinced there's any problem with the governor with what I've seen. Either way, I've learned a lot in this thread thx for your help. Any more suggestions are always welcomed.