91L98Z28

Have a question for all the tranny experts...

I just purchased a 91 Z, 5.7L/700R-4, has 85k on it. Runs great overall, but i'm looking to firm up the tranny just a bit. I don't need or want it to chirp the tires (even on WOT shifts), nor do I need to change the shift points. Basically, i'd like crisp shifts at WOT (without chirping tires!), moderately firm at mid-throttle, and stock or near stock when driving normally...if such a thing is possible. Basically, I just want it to shift a bit more "sporty".

From reading the past posts on shift kits, it looks like I should get the TransGo shift kit. But, I can't really find GOOD info on this kit. It seems like a do-all kit: some advertise it as a full manual kit, some advertise it as a mild kit, some advertise it as being both. Is it a multi-purpose kit, where you pick and choose the parts to put in (based on some worksheet or guidance supplied with the kit) to achieve the desired outcome? If so, will the kit include the parts I need to achieve the tranny performance i described above?

I also keep reading about corvette servos, valve sizes, and stuff like that. Just what do these parts do, and would any of them be a better way to get the performance I want?

If it matters, I'm not really interested in taking the tranny out. I want to do what can be done with the pan off with tranny in the car.

Oh, and I've already checked the TV cable and it was adjusted properly.

thanks!

Pro Built Automatics

The Trans-Go Green & White Box Shift kit can be modified to do exactly what you want, mild shifts at part throttle & firmer shifts with more throttle. Let me know if I can be of help.

91L98Z28

What Kind of modifications would these be? How would the tranny perform with the TransGo kit installed in the "mildest" way possible in an un-modified, out of the box way?

thanks....

91L98Z28

Also...
John Millican said in a post on the 20th (4 days ago): "I do have to do a manual downshift after about 55mph due to the design of the transgo kit, below 55mph it will automaticly kickdown with throttle."

Does the TransGo kit have an option to NOT do this? If I am at 75mph and go to 100% throttle, i want it to downshift to 3rd and stay in 3rd until it hits the normal shift point (~5200 rpm) and then it should go into OD (and stay in OD even at full throttle).

I don't understand why the trannies and shift kits make such a big deal about OD. it's just another gear. It should shift between 3 and 4 the same way it does between 2 and 3..... downshift on acceleration, upshift when necessary because of RPM or under light load. at least - that's my opinion. I prefer a "4 speed automatic" over a "3 speed automatic + special extra gear".

nick

Pro Built Automatics

The 4-3 downshift passages are in the plunger sleeve and is preset at the factory as to where they want it. There are different 4-3 passage locations (as to how hard or easy it will be to make a 4-3 downshift) in the different applications of the 700R4. In 1992 the Corvette had these passages eliminated. You can block these passages with two small allen screws, some grinding will be necessary on the allen screws to clear the plunger & bore. Now once you get to about 65 mph, you will not be able to get a 4-3 downshift without manually moving the shift lever. This can be done without removing the valve body.

91L98Z28

OK, so assuming I want factory-style 4-3 kickdown, I will need to leave the plunger sleeve alone. (Normal highway speeds around here are above 65 and I don't want to be manually kicking it down to pass etc.)

With that said....Can the TransGo kit be installed without altering the plunger sleeve? Or is it going to alter the 4-3 kickdown some other way?

thanks for your help!
nick

Pro Built Automatics

The Trans-Go Shift kit will not alter 4-3 kickdown, it will address other problems such as a sticking TV valve, 1-2 part-throttle bang shift, etc. If you install the Trans-Go Junior Shift kit (as is) this will in most cases improve the shifts as to smoothness, if you are looking for some performance out of this and still keep the smooth shifts at part throttle?, it can be done. Give me a call if I can be of help?

91L98Z28

Well, Now i don't know if this tranny is even worth messing with.

As mentioned I just bought the car. I checked the tranny fluid this morning, and it was slightly below the hashed area on the dipstick. I added almost a full quart to bring it to the top of the hashed area (tranny heated up, in park, engine running). The overall part throttle shift quality improved quite a bit, and i'm happy with it in that way now (part throttle drivability). the shifts are quick and positive (not firm, but normal).

Now the problem...Because i wsa never happy with the shifts before, I hadn't done a WOT run. After adding the fluid I went WOT in 1st. the 1-2 shift didn't seem to happen. The rpm started "smoothly" dropping (from about 5200 to 4800) over about a 1.5s, but a shift never happened, so i got out of it for fear of burning/breaking it. As soon as it shifted to 2nd (after I got out of it), I again went to WOT and it held just fine (no slipping at all). It will also hold just fine on a 3-2 WOT downshift.

Thoughts? Is something in the tranny toast? thanks again for all your help.
nick

TP355Z

I've got a question fellas - how 'good' is the 700-R4 anyway? I've got it in my camaro (about 330hp) and I think it has a shift kit in it (it bumps pretty hard) so do i have something fun? I dont wanna spill my guts on the floor if i put a 3.42 posi unit in...lol

TP

91L98Z28

Well, *I* am definately no automatic expert, but from what I've read on the boards, how "good" it is just depends on what condition your specific tranny is in, and what modifications have been done to it! apparently any old shift kit can make it shift hard (like the B&M) but may not necessarily make the transmission better able to handle power, but if there is nothing obviously wrong with it now, i guess all you can do is put that rear end in and try it?

F-BIRD'88

Install the transgo shift kit. It will address the delayed upshift.
(slow tv pressure rise) Also these transmissions are real sensitive
to fluid level. Be sure the fluid level is right up to the top
of the "full" window on the stick. I run mine a 1/2 qt. over that point and noticed a nice improvement in a pesky delayed or no 2-3 shift. (fluid starvation at WOT [high Gforce]). Do not exessive overfill. It won't help beyond that and may damage the trans.