sami85L98

Pete,

I have a Mad Dog 700R4 tranny works pretty good except few things as follow: 85 vette rebuilt mad dog tranny, automatic.

> While cruising on hwy at 65-75 mph if someone pulls beside me or challenge me or if i have to change lane quick, i cant do it quick b/c even after depressing gas pedal more than half it dont downshift to 2nd or 3rd and even it downshift but not quick takes time to downshift.
> 1-2 shift pretty hard and it bangs gives a big jerk.
> 3-4 is not really firm.
> while racing or cruising hard at wot it upshift to 4th too soon (feel no torque or firmness) and in a second shift to 2 or 3rd than goes.

Following things i would like to do.

> Installing a TV valve spring, .500 boost valve and a PR valve so that it will increase line pressure.
> Installing a 4th overdrive gear billet servo to feel firm in overdrive, mad dog lou did not suggest me to use billet servo's but i did not got any satisfying answer.
> Installing Transgo Shift kit 2 to remove that bang from 1-2.
> Installing a Corvette governor or removing one spring from my existing governor to delay shift points.


Will u suggest me is iam going in right direction or do u have any other idea to solve above problems.

All the parts mentioned above have already purchased long time ago but never installed.

I appreciate and thanks for ur input on this.

Also going for SR setup in a week or 2.

Pete K

First, I would recommend installing a new spring in the tv valve. This spring is often reused and should always be replaced. A weak spring will cause the delayed downshift.
The 3/4 shift could be a servo issue. gm used 3 servo's that I am aware of. I use the vette servo in everything. The .500 boost valve goes hand in hand with the vette servo(as far as I am concerned) I have never needed the billet servo's. Vette servo works fine for me. The servo pin length must be properly set using a selective pin. If the selective is still too short, a pin extender can be added. This requires a special tool to check. If pin length is wrong, it will be impossible to have nice shift quality. It will also burn the band. You would be suprised how many shops do not own the tool to check it.
The 1/2 bang is probably the result of locking the accumulator with a solid sleeve. If this is the case, remove sleeve and install a white(firmest) or green (very firm) spring.
Rather than monkey with the governor, I suggest buying a new gm vette governor or a Sonnax 730 vette governor. They are identical. They both give approx 5200 rpm wot shift points.
Most shops that sell $500 or so transmissions cannot do everything to convert a trans to vette standards. It takes the profit away. Most cheaper shops cut the output shaft, move the speedo gear and call it good. If this is the case, you will need to do these things to be happy with your unit.

Redeasysport

I had problems with thier trannys had to change the governor from my Vette tranny to get it to shift right.The hard shift 1-2 is gonna be a backyard shift kit .It is done by plugging an accumulator and drilling some holes.If your original tranny is still around I would change both the governor and valve body from your original tranny to regain your shift points.Thats all you should need as well as a proper TV adjustment to factory specs.
http://www.tvmadeez.com/

Pete K

Be careful interchanging valve bodies. 82-early 87 interchange. 87-92 will interchange 93 is year specific. The check ball arrangement is specific to the case(worm track) and valve body combo. Also early 87 and up uses specific seperator plates. each model year has approx 20 different seperator plates. It gets confusing quickly. One wrong check ball or seperator plate will kill the trans.

ANTI VENOM

I would stick with Pete on this, but just for reference, I installed a Transgo Reprogramming kit with a .500 boost valve 9 disc clutch pack, billet servo etc. etc.

My 1-2 shift will spill your coffee
2-3 is nice and firm and
3-4 turned out real nice and it is fast and firm.
It shifts quickly with or without manual input, and I am relatively happy with it. Someday I will tone down the 1-2.
Good luck with your tranny!

sami85L98

Pete thanks a lot and what a detailed and fine explanation , u must have really spent some time on kboard. First i dont know what servo in my tranny mad dog said its got vette servo but i dont believe that, and about valve spring i dont know its new or used one, and last about valve body again i dont know may be its from a truck or Suv or what year it came from and i dont have original tranny nor valve body. Apart from all these problems tranny works great spcially after 2800 rpm or 75 mph it pulls damn hard without any problem and one problem i forgot to mention my mileage drops to 19 in city used to be around 23.

As u said i will do the spring and vette servo and vette governor and from there i will see, still any problem than its gonna have a new valve body from 88-92 along with transgo kit.

And again thanks every one. One more thing mad dog do not check pressure or any kind of particuler checking, they just do test drive to see shift points stuff like that like a trial and error method.

sami85L98

Also wher e i can get a new or used valve body from 88-92 ?.
is anybody has a spare valve body.

Redeasysport

Well since you do not have the original corvette governor you will have to play with the governor adjustment.I believe Maddog will send you the kit for free and mabey a new Corvette governor.Even though I had issues with his tranny I did get his second one to shift right.They were straight with me while I worked with a local shop to "get it right" but it never got there so I had my old one rebuilt.Anyway call them and explain the issue and they might pay to have it done.

sami85L98

mad dog loui is very straight guy i have no complaint for them, this is the second tranny they rebuilt for me and installed for free, he is very nice guy and infact he sent me a governor caliberation kit for free but i messed up setting those wieghts and springs. At wot it shift at 3200 rpm, i called him and he gave me instructions but still i messed up. thanks for ur input. His new c6 Z06 is awesome make me jealous.

Pete K

Are you absolutely sure that the trans is an 88-92 unit? It is date coded on the pass side pan rail. If you post the info i will break it down for you. If I had one laying around, I would mail it to you. Unfortunately, I do not have any at the moment. I cleaned the shop up. The valve bodies and pieces inside are no longer sold thru GM. I have run many numbers and come up discontinued ever time. Sonnax is the leading aftermarket supplier of trans parts for your unit. They furnish ac-delco with many, I have been told. Your problem regarding short shifting may very likely be in the tv valve. After all your recent grief, *I* would simply stick in a vette governor, a new tv spring , reset the tv valve and go from there. If you dissassemble the servo and give me the gm numbers off it, I can Id it as vette or not. If it is aftermarket, It will have no numbers. I can help you Id it by measuring. Don't give up, you can fix it.

sami85L98

Thanks pete, i would have buy it right away when u post ur tranny was for sale before u ended up with ur niehbour or friend.
Mad dog said mostly they use 88-93 core but dont know, Well its alright i would do the thing first as said me tv valve spring, vette governor. I already bought a vette governor, lo/rev boost valve and a corvette servo from transmissioncenter.com i should have it here by early next week.
I bought a vette governor from thier web site before and it was shifted at 5200 rpm range and i think readysport or some similer CF member bought that one and his problem solved and he too bought tranny from mad dog, but what i have to do that 1/2 "bang" bothers me too much specially if i cought in heavy traffic and i live atlanta its traffic everywhere. I work 7 days a week wish if i had a couple of days off i would have visit you,

Infact i bought that accumulator spring too (white) all these parts r actually cheap. I had another tranny bought from mad dog as a spare that thing bang too in 1/2.

Pete if u check transmissionhead.com they r selling 88-93 valve body for $189 dont know if that comes from vette or truck or van though. Also mad dog installed AUX valve body in my tranny.

thanks pete. I will let u know when i did this update's otherwise tranny working fine specially when iam on hwy, in town its ok but not really torque feel and 1/2 bang too much every time it downshifted to 1st gear.

sami85L98

Pete i just check other spare tranny i have the date coded is 86 written too small within a circle trade mark thats the only i saw and others are written 17 big letters . So, i assume the tranny i have in car right now probably 86 or may be 88 or 92 but they have installed AUX valve body in all thier trannies.

Pete K

The round circle with the date is the day it was cast in the mold. It does not nescessarily mean the vehicle year. That code is on the passenger side of the trans stamped into the pan rail. You may not need a valve body though. Do not buy one yet. The 1-2 bang is probably the spacer in the 1-2 housing. Next to the valve body is a round circle that is about 2 1/2 inches around. 1 long bolt and 2 short bolts retain it. Pull these bolts, remove the spacer and install the white spring. This should give a firm but not too harsh shift. White spring is typically used in h/d or 4wd pick up trucks. In my opinion, a perfect spring for the vette. It sounds like you are well on your way to solving the problem. Keep us posted.

sami85L98

pete if possible will u call me at 404 822 8070 sami. I dont sleep until 3 am. thanks

koaea

This is probably a stupid question, but are the 4L60 and 700R4 basically the same transmission? I've been considering getting a transmission from Maddog Lou, for another car (not my vette) that currently has a th400, but I'd like to have another gear!

thanks

Joe

Redeasysport

Same animal

Sami

You might call Lou and ask if he will pay to have it done for you especially setting up the govenor.He did for me.

Pete K

Sami, Returned your pm. I will give you a ring later this evening.

sami85L98

Loui already did too much for me and if i ask for anything more it would be sure embrassing me, rebuilted two tranny for me and plus two governor's and a caliberation kit for free oh man thats too much, i will just leave him alone, he is a heck of a guy though.

comp

Vetteran

I have a buddy (no internet) who has a C4 with a 700R4 tranny. The problem
hes having is, it will not shift into overdrive while crusing down the highway
or anytime for that matter. Plus he has told me the car has to be good and
warm before it shifts into third. A friend told him he needed to hookup a
switch so he could enable it! I'm not a C4 guy, but that sounds strange
to me.

He took the car to a couple of transmission shops but they didn't know any
thing about it. Anyone have any ideas and/or possible course of action?

Thanks folks!