garrettb

Today is the day I am going to park the car for the winter and start working. I have three big things on my list, and I plan to post updates and photos as I get them done.

1. Remove the TH350, rebuild my 1988 4L60, and reinstall.
2. Remove batwing, rebuild differential, and replace all the rubber bushings.
3. Remove throttle bodies, ream, install bushings, and balance.

This will be a lot, and I am definitely looking for advice along the way. I was going to just take the 700R4 to a local shop to be rebuilt, but they were quoting me around $1000. I can buy a kit myself for a few hundred, so this seemed crazy!

Today my plan is to head to Menards and buy some wood to start making four crib blocks (no car lift here!). I know I need at least 18" of clearance, so I'll have to do some planning first. When I remove the transmission, will the engine balance well on its two side mounts? Is a block needed under the oil pan to support it? The manual mentions lowering the trans while it is still bolted to the engine to aid in removing the cooler lines, but I don't want to break my new engine mounts! Sorry if these are dumb questions, I just want to do this right!

Here are some pictures from a few weeks ago, just because a thread with no pictures is boring!

Gordonm

Who replaced the original trans with a turbo 350? It should already have an OD trans in it.

Yes you will need to support the rear of the motor. Just a wood block is fine. It is not heavy at the back but it does need support. The mounts will flex a little but don't go overboard here.

BTW nice looking car. I have always loved the looks of the 82. They are great cruisers with the OD trans. Not a real barn burner in HP but when the cross fire is setup and working good they are not bad for a driver.

Kipring

I'll be watching the differential rebuild. I'm hoping to swap gears in mine sometime soon. Thanks for posting pictures along the way!

garrettb

I'm not sure why this car has the three speed in it. I'm thinking the original 700R4 got roasted somewhere along the way, and then the TH350 made its way in. Thankfully, no modifications were made to the frame during the swap. I bought a 1988 700R4 with the 30 spline input shaft and auxiliary valve body, so it should be more robust than the original anyway. I just need to get a torque converter figured out.

I spent the afternoon cutting, and ended up with this. I think I am going to assembly each in two parts, that way they'll be easier to use when I take the car all the way up.

I appreciate the kind words, Gordon. I bought the car to drive it, that's why I'm doing my best to make it as road worthy as I can!

derekderek

you raising your car or playing Jenga? I would think 16 cement blocks, 2 wide 2 high with holes facing up not sideways would be more stable. 9 inches each. get you the same 18 inch height.

garrettb

I kept thinking that same thing as I was making cuts. I actually thought about using cinder blocks, but I remember reading something about variations in quality (scared me away). Anyway, these things will be built like tanks when I am done assembling them. I'm going to glue each joint along with the screws. I may also use a few carriage bolts and corresponding holes for a kind of "alignment pin" thing for my two sections. I don't think I'd be able to get the car under it in one go if these things were full height.

Buccaneer

Very nice looking 82. Odd that the 700R was removed at some point for whatever the reason. Other that the trans, is the rest of the motor/car bone stock?

Good luck with your winter project and waiting to see how it turns out.

derekderek

Buc, you mess with tbi's? I have a pair of 2 inch 454 units with oem adaptors and injectors.any use for them?

oemtech

Buy my 82 parts to start with... https://www.corvetteforum.com/forums...nuals-doc.html

garrettb

I'm guessing whatever shop did the swap had one on hand, and convinced a previous owner to go for it. Regardless, they used a spacer at the tail end to give it the same overall length as the 4L60. I knew something was up when I saw the lockup connector just dangling there!

Yes, besides the transmission, everything else is stock. I guess I upgraded the sound system, but if you don't include that, I haven't made any permanent modifications. I really like the factory look/equipment. Engine is untouched as well apart from the smog pump removal. I also had the exhaust manifold air injector tube holes welded. EGR is blocked off because I don't have a solenoid that works. I guess that was also the reason for taking the smog pump off. The solenoids were either cracked, or the actual coil was bad. It's really hard to find these one year only parts!

In other news, I got the Jenga set done. They're extremely sturdy. Now I just have to figure out how to get the car up there!

garrettb

Lots happened today. I apologize in advance for the unorganized photos. I don't know how to link them directly into the post.

I power washed the exterior before disassembly, and still made a mess. Oh well. I bought this thing for something like $50 and figured I had nothing to lose. The guy I bought it from had never run it, but he said something about it just being rebuilt, but not having 3 and 4. Either way, as I was taking it apart, nothing terrible really stood out. All the clutches seem to have all their material left, and no chunks of metal anywhere. I tried to take photos of the wear I thought might warrant more investigation. I need someone with a more trained eye to tell me if these parts are worth reusing. For example, the sun shell and reverse input drum show some wear, but I don't know how much wear is acceptable. The splines on the input shaft also show wear, but I don't know what's normal.

Take a look at the photos and let me know what you guys think. I am still trying to choose a vendor for my rebuild kit and torque converter. I can't find any information regarding stock stall speed, but because this will be a driver car, I am looking at around 1500 RPM. Any input here would be appreciated as well!

garrettb

I ordered a lot of new parts today. I also found the issue as to why this transmission was "retired." The 3-4 clutch pack was burnt to shreds! I bought a new 3-4 piston to help solve that from happening again. I ended up buying a super rebuild kit with Borg Warner frictions, case electrical connector, manual shaft, pan bolts and pan, input drum with shaft, reverse input shell, sun shell, and a few other odds and ends. I want to do this right, and having the right parts will go a long way.

Now comes the only thing I have left to buy. The torque converter! I need help, because every manufacturer I have researched seems to have some sort of "issues" and I don't want to ruin my new transmission. I want an OEM, 1400 stall, lock up converter. Any suggestions for brands out there? I am all ears!

NeverTooOld

I buy all of my automatic transmission parts from TranStar as they have locations all across America. The TH700R4 torque converters come in three available stall speeds; 1600. 1800, and 2000 rpm and three different clutch materials; synthetic "paper", carbon fiber, and woven carbon fiber.. About $90 exchange. For average street use just buy the 1600 rpm stall and paper clutch material...

garrettb

Thanks for the suggestion. Advance Auto was having an online black Friday type sale, and I ordered a torque converter from them. If I don't like the looks of it, I can always take it back to the store. At $80, it was almost too good to pass up. It's a Pro King, which is made by TranStar. 1400 stall with lockup. We will see what it looks like when it arrives!

garrettb

I couldn't help myself but to get the car up on my blocks, and start tearing things apart. All went very well overall. Transmission came out smooth, and my $80 Harbor Freight transmission jack worked flawlessly. One man job all around (except the help from my dad in removing the exhaust)!

To my surprise, the driveshaft universal joints were actually spicers, and moved very smooth. And as I suspected, the differential lower cushion was completely flat and not providing the cushion it should. From what I can see though, I have to have the rear wheels off the ground to remove the differential, so that will come after the new transmission goes back in.

The only snag I ran into was with the cooler lines. I have copper lines installed, and never thought much of them until it came time to take them loose. I then did a google search on replacement lines, and basically came to the conclusion that copper lines should never be used as transmission cooler lines. Do I really need to shell out $100 for new reproduction steel lines, or can I make new copper lines? I had to cut the existing ones because of how stuck the nuts were. From the looks of it, these lines never leaked.

I now have to do some detective work on the TH350 that came out of the car. It looks like they used the original 700R4 tail shaft, installed a spacer between the housing and tail to lengthen things, and then chopped off the output shaft. From what I can tell, no modifications were made to the crossmember or driveshaft. I'm pretty lucky! From the ATSG 4L60 transmission manual, the output shaft I have with my new transmission is a "long spline" shaft. The other types they list include: corvette, short spline, 4 wheel drive, and syclone. Can anyone provide me with any additional information here? I would love to not have to buy a new output shaft too. That's my update for now. Enjoy the photos!

81vettski

Good looking ride and congrats on getting it started. You were not kidding about that lower cushion. It is obliterated. Curious how you got the car up on the blocks?

Buccaneer

Funny, I was going to ask the same thing.

garrettb

My blocks are each two separate sections. The bottom section is probably around 11 inches, and the top section gets me the remaining 7 inches. I have two "high lift" floor jacks that can lift to approximately 20". I lifted the front of the car, placed the first set of blocks, then lifted the rear of the car to place the first set of blocks in the rear. Next, I grabbed a heavy duty metal cart (what the crossmember is sitting on in the last photo of post #15). I placed the jacks on top of the carts, because they can't lift high enough sitting on the bare floor. Again I raised the front of the car, stacked the top half of the blocks, and repeated with the rear. Not too bad of a process, just slightly time consuming. Actually, the hardest part was making the blocks!

jim-81

cool! I am going to have to make something similar when I attempt to check driveline angles after installing the TKO.

jim-81

Question - did you need all the height of those blocks? Could they be a little lower?