Ken73

I've got an '82 Vette with the original '82 700R4 in it - it's crapped out for the third time now, and I'm fed up with paying $1100+ to have it fixed each time.

I've purchased both the ATSG manuals and I already have the Haynes GM Auto Trans manual, so I'm confident I can rebuild them. I've been checking out www.bulkparts.com for parts, but it seems like I'll have to upgrade some things.

I definitely have problems with the 3-4 clutch pack - that went out after 1 year. I could drive in 3rd until I was ready to "drop" it into 4th, and it ran fine. I couldn't just put it in 4th and leave it there; it would freespin and barely upshift if I did. It finally lost 3rd gear and barely goes into 2nd (if at all) now. I've got 1st and reverse, no problem.

So after talking to one of the sales guys at Macko (above,) he said he wouldn't even touch an '82 700R4, that it's like "starting off with a problem" and that it's a huge PITA to select all the right "upgrade" parts.

My question is - should I find a junkyard 700R4 from '88-up, and rebuild it - or can I stick with the '82 700R4 and do some basic upgrades that will make it last longer? Can the '82 unit be beefed, or do I *have* to go to an '88-up unit?

Keep in mind, I'm doing a motor rebuild/teardown and will probably have 350+hp and over 400ft./lbs. of torque. I'm wondering if I get an '88-up unit, will I still have to buy a bunch of other upgrade parts to make it last, or can I get a good "master overhaul" kit and be done with it? (Obviously this would depend on the condition of the trans I get from the junkyard, too.)

Jay 727

I think you could make it work with enough modifications and upgrades depending on how much power you have. But it would be much easier to get another 700 to start over with. I've picked up an '89 for $20 because it was missing the tail housing, the typical 700 core goes for $45 around here. When I rebuild a trans I find it very useful to have a few cores to work with for spare parts.
Keep in mind junkyards have a core pile of transmissions they think or know don't or may not work and these can be picked up for cheap. A trans out of a vehicle can go for more money but be in the same mechanical condition of one in the core pile.
I have picked up a few cores that only need a basic rebuild.
See what your local junkyard has to offer.

TomP

I think I agree with your mechanic; back then, the 700r4's had 27 spline output shafts, in '85, they received 30 spline shafts. (Or was it the input shaft? Sorry, not enough coffee yet to remember!) Like Jay said, you can always give your trans some of the upgrades, like the enhanced accumulator pistons (they retrofit, and drop right in to an older 700r4)- but I don't know if you can change the shaft without a ton of trouble. I'd vote for getting as new of a 700r4 as you can from a yard!

Don't the Vette's use a different tailshaft, though? If so, would his '82 tailshaft bolt on to a newer 700r4? (Don't see why not, but figured I'd put the question out)

Ken73

I'm the mechanic.... (I have 3 C3 Vettes, I *have* to be my own mechanic!) This was a guy from the parts place; www.bulkparts.com . He just expressed his personal opinion, which I appreciate the honesty, but I don't know if I have time to go yank a junkyard trans out. It's a bit time consuming, really. Maybe later on down the road if this one doesn't hold up. I'll install a racing kit in a junkyard one and go from there. For now I'm going to rebuild my current one.

The '82-'86 transmissions have a 27-spline *input* shaft, hence the reason for getting a whole new torque converter for the later models, which have 30-spline (thicker) input shafts. There's no upgrade that I'm aware of, and even then, I'd have to get a new converter.

It's actually the '84-'96 Vettes that have the funky tailshaft, they actually have a C-beam that connects the transmission tail directly to the differential - completely eliminating any crossmembers underneath the car. Mine is an '82, the old C3 body style, which has a crossmember just like any other car. The '82 is the only C3 that came with a 700R4 though, which is why most people talk about the "Corvette tailshaft" as being weird (they forget about the '82.)

I'm thinking of doing some of the upgrades, such as the servo, kevlar-lined band, enhanced 3-4 clutch pack (9 frictions instead of 5 or 6 I believe,) and a 10-vane pump. I think there's also a couple of "boost valves" that go in the pump assembly that are larger. Not sure what they do, though.

I'm definitely going to have my converter rebuilt; there's a guy here in town that said he'd rebuild it with Kevlar linings on the converter clutch, which I'd much rather have. My clutch doesn't seem to engage, but that could be a problem elsewhere.

I think my biggest problem is that my 3-4 clutch pack dies too quick, sends a bunch of metal into my trans, and then it slowly eats itself over time with all the metal shavings in there. That's the most important upgrade I'm going to do, along with a 3-4 WOT upshift fix (which is a very simple fix.) I'm also going to put an external cooler in, and bypass the one in the radiator (since I live down here in the hellish heat of Houston.)

Tell me more about this enhanced accumulator piston..?

p.s. Jay, my motor is going to have about 400ft./lbs. of torque up to about 4500 RPM, where it drops off. Roughly 350+hp, approximated.

Jay 727

This is just my opinion but it's actually less time consuming to build it right the first time. Hasn't it been time consuming enough to rebuild your '82 unit for the fourth time? You need to sit and think about it for a while. And at $1100 plus each time.
I have to wonder how much more it could possibly cost to find a junkyard that will pull one for you or just buy a probuilt trans.
You say $1100 each of the three times to rebuild an '82. That is down right stupid. (sorry but the truth comes out sometimes).

Ken73

I don't disagree that - I say 3 times, but it's only been once for me, twice by the previous owner. So I've only put $1100 into it once, hence the rebuild.

Right now I'm on a tight budget, and I don't really race the car; so putting the '82 unit back in isn't that bad for me right now. I figured I'd build the '82 unit up strong for now at a bargain price, then find a junkyard unit later.

If I can call around and get a pre-pulled unit cheap (under $100?) I might go ahead and do it though.

Jay 727

Junkyards are insane, I've gotten prices in the range of $750 to $125 for pulled 700's. And this was about five years ago. Now the minimum price has gone up. I don't know the junkyard situation in your area but if I were in a situation like yours I would get a couple of $45 cores in the '88 to '91 range and build one out of them. You won't need as many upgrades so that $90 you spend could be saved. That is of course assuming you can find cores for a good price.

transfixleo

Here is how I would handle it: I would USE that unit but upgrade the internals. If you can score a good later core for parts, great. Use the Pump and Input Drum but put the Boost parts from the original in the new Pump. If you get a Rear Planet with the Oil Dam use it, otherwise get one and use the rest of the Geartrain from the late unit. Install a NEW GM Sun Shell. Install a TransGo Reprogramming Kit and Hi Rev Pump Ring Kit. Skip the Kevlar stuff. Upgrade the 3-4 Pack to the 4L60E version and use High Energy Frictions throughout (all Borg Warner). Use quality Dexron or full Synthetic ATF (NO "special" oils). TruCool Cooler and bypass the Radiator.

Ken73

What if I can't, or can't get the time? If I score a later model unit, I'd much rather rebuild it instead.

Saw that, looks to be reasonably priced - $40 or so.

Definitely going with the TransGo Reprogramming kit. Have been reading lots of old posts and I notice that's what's recommended. I read the explanation of differences between it and the B&M kit, and know to stay away from it (the B&M kit.)

Bulkparts.com sells a "high performance 13 vane pump kit" .. is that what you're talking about (or equivalent?)

How come?

Will the "commercial" 3-4 clutch pack that bulkparts lists work? I believe it uses 9 frictions and 9 steels - is this the same thing..?

I planned on that; the kit I'm looking at uses Borg Warner frictions.

Down here in this heat I definitely planned on bypassing the radiator; in fact I was looking at a cooler with a built-on fan already. I generally don't mess with the "special" oils as they're usually there to attempt to cover up a problem, not prevent anything. Is the synthetic any better..?

transfixleo

The thing about that unit that makes it desireable is that it will have the Hi Rev calibration in it. It still has it's problems and a TransGo (full) Shift Kit would be needed on top of the Reprogramming Kit to correct some timing issues.

No the 13V kit is not what I am talking about. This will shock allot of people but I really don't give a hoot about that stuff. Give me an old seven vane pump and let me set it up my way and I will put it against any 13V Pump. I am talking about the TransGo Hi Rev Pump Kit that corrects the Hi RPM pressure loss and destroyed pump from broken Pump rings.

Skip the "Kevlar" band because it is not as good as the B/W Hi Energy Band.

While there is nothing wrong with the Alto (commercial) clutch pack I do not think it is a good as the 4L60E setup. Now if you want to mix the two you could do that but with the stock 4L60E setup, TransGo Hi Rev Release Springs and Reprogramming Kit you will be just fine and if you are really pushing a lot of power you can use the 4L65E Frictions and earlier steels to get 8 Hi Energy Frictions.

The Synthetic is great at handling heat and stays stable at any temps you are likely to see. It will help keep the Tranny cooler and properly lubed.

As for not having time, well it takes time to do a later model unit too, right? I didn't say this was going to be easy, I just said this is how I would handle it.

Ken73

Can you explain the "full" kit? There's three kits that I see - the Reprogramming kit, the shift improvement/correction kit, and the "Jr." kit. I was considering the middle one (the improvement/correction kit.)

Okay, I see that now - "Transgo High Rev Pump Kit" .. The only thing is, I'm probably NEVER going to rev over 5500 RPM. Do I really need this, or is it just a wise protection-type thing? Would the 13 vane pump be a bad idea in conjunction?

Really? Interesting. So I should get the B/W one that's the original size (not wider?) It says "updated design" ...

I'm not seeing the 4L60E frictions.. they just have "82-up" frictions for the 3-4 pack. I do see a slightly more expensive kit called the "3-4 Power Pack" that has 9 Red Eagle frictions and 8 Kolene steels..

That's important to me! I want this to last. It's not going to be a midnight dragster, just a daily driver with some oomph behind it. Once in a while I'd like to race it though. I'm definitely going to get a trans cooler - possibly one with a fan already on it, even.

That's why I posted in the first place.. I wanted to hear some opinions! Like I said, I want to build this one up so I can get my car running and I can drive it for a while - then I'll take my time and build up a later model unit nice and beefy. I appreciate all the input!

TomP

Back to the top; I'm curious as to those questions, too!

transfixleo

The Full Shift Kit is not the Reprogramming Kit, which you also need for performance, but it is the opposite of the Jr Kit as that one does NOT include the timing corrections as it is meant for the later units that were OK from the factory.

If you really don't intend to go over 5500 then get the Normal TransGo Pump Ring Kit but their pretty much the same price so why you wouldn't want it is beyond me. I know the 13V is the current "must have" on the boards but if you have a later core with a good 10V you are fine. As I said before I've setup old 7V Pumps that work just great. I prefer to put my money where it is needed most.

Can't help you with what your choice of supplier has or doesn't have. If you are intent on using the Alto Kit, so be it. If you want the correct parts, drop me a line as I can get anything. As for the Band, I already stated to use the B/W High Energy Band.

Get the TruCool (available to you under B&M SUper Cooler).

Ken73

Cool. I see both - the "Shift Kit" is ~$81 and the "Reprogramming Kit" is ~$38. I need both for performance.. got it.

Think I'll get it anyway, it's only $10 and is cheap insurance.

Actually the kit says it has Borg-Warner frictions, and "thin steels." I e-mailed you but not sure if you got it. (I used the e-mail address on here.) I found the Borg-Warner band, it's ~$11.

They have the TruCool coolers, just not sure what size I should get. This is for my '82 Corvette - which doesn't really have much room anywhere for a cooler. Any suggestions there? I'm thinking of getting something with a small fan on it, primarily because I drive in traffic a lot.

transfixleo

If you can't fit the small TruCool you won't have room for a fan either. You can use the 14,500#. It is small and very effective.

As for that kit it will not have the high energy 4L60E Frictions. You will have to piece the kit together.