okay I've been reading for an hour in the search section:
i still have questions. I know what you need to swap a th350 in,,...but will it work with the speedo, computer, cables, converter, shifter, etc,.. what micellaneous stuff won't work?,.. or will it all work.? thanks

 

I just did my swap this past weekend. The TH-350 will bolt right in. But you have to modify the trans mount bracket, because the trans mount of the th-350 is a little more infront thant the 700r-4,about 1-1/2 inches. The stock driveshaft will work as long as the th-350 has a the 9 inch tailshaft. The shifter bracket will need to modified in order to attach it to 2 trans pan bolts to secure it down, but it does work with the th-350 shifting. As for the converter, i'm not too sure if it will work. The speedometer works with the th-350. You will probaly need to make a dipstick tube, because the location on the th-350 is farther back than the 700r-4. I have no problems with the computer. You will have to get a kickdown cable. I chose not to put one. Its a good idea to change the u joints on the driveshaft too. You need to fabricate or buy a kit to attach the torque arm to the th-350. But overall the swap I did was pretty easy. Good luck with yours!

 

Okay the deal I'm working on is as follows. It is a shorter than 9" tailshaft,.. but he has the new driveshaft and all of the other hardware needed to bolt it right in including a mount for the torque arm. it is a full conversion kit w/ a converter.
my questions:
1---Will they have a kickdown cable that fits, and you said you don't use one? don't you need one?
2---i can modify my tranny mount bracket no problem?
3--so my stock shifter will work if i modify the mount? will that be really hard to do?\
4---if i wanted to, could i later switch the tailshaft easily to use my aluminum driveshaft?
5---it's geared 2.52, 1.52 and 1:1.
I have 3.45 rear gears, what rpms will i be at whe i'm driving on the highway? thanks.

 

Some answers to your questions:

1. The purpose of the kickdown cable is when you stomp the gas pedal the trans downshifts (some call it passing gear) and it also controls how hard the trans shifts. Companies (jegs, summit) sell kickdown cable kits. If you don't run one be sure to block the hole.

2. You can modify the trans mount easily. When I did mine the trans mount bolt was about 1 inch off from the trans bracket hole, so I drilled a new hole on the bracket.

3. All you have to do is weld an extended peice to the orginal, because the stock mount is about 1 inch to short.

4. As for switching the tailshaft I am not too sure, but the trans mount location wouldn't change.

5. I still have stock gears (2.73) and do about 60mph at around 2000 to 2500 rpms. Since your gears are lower it should be higher around 2700 to 3200rpms. Which sucks if your planning on doing long cruises on the freeway.

 

well, thanks a lot for the info, I might not get the tranny after all. thanks

 

I beleive to make a TH350 work on an 87 gta you need a speedoi converter..... Because the GTA needs an electric signal not a manual one.... I had to do the same thing for my TH400 its just a little box that screws into the cable driven speedo sensor and converts it to the early GTA wire driven signal...

 

If you don't run the kickdown cable on a th350 you'll have to shift manually to get it to shift right?

I am thinking about getting a th350 myself. Im gonna get the extreme duty driveshaft, and a spohn torque arm if I do thought. Expensive pieces but much better than the stock stuff.

 

i'm deciding not to now,.. i think i'll need over drive