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'63 Riviera 700R4 trans.


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Guest 63riviera
Posted

I just got my Riviera back from Bendtsens Transmission (which makes the adpaters), which did a complete conversion that was quite expensive

Now, there's even more slipping--much worse than than the old, tired dynaflow. The engine must rev up to 3500+rpm before it shifts into second. And the shifting is very erratic and rough. The engine runs great and smoothly.

After getting to 55mph, the car's rpms do drop. But if i accelerate, the transmission shifting and transition is extremely rough.

Obviously I'm bring the car back.

I wish I never had all this done, and just rebuilt the dynaflow.

Has anyone else experienced this problem, or have experience with the 700R4 transmission?

Posted

Hi

I also have an 63 Riviera, and i am not really happy with the dynaflow. I think a 350 or even 700 would be a better choice and i also plan to change it, however i am from austria and here its much more difficult and expensive to do this.

how do you fix the problem with the starter? it on the left side isn´t it? and all other transmissions have the starter on the right side. and please keep me up to date, so i will not make the same failure like you. Furthermore i will make myself a christmas present and get a new carburator (Edelbrock) and i don´t really know if its better a 600 or a 750. On buickstreet.com they suggest a 750, but all in other forums they suggest just an 600. so the question is, if an 750 brings that much power, and therefore it is worth paying 20% more for gas or not. In europe petrol is way more expensive than in the US,(around 1,1?.-/L)(i don´t know how many gallons that would be) so for me this choice is quite important.

greetings from austria

Alex

Posted

Hey Alex,

The formula for CFM is CIDxRPMxVE divided by 3456

According to my Edelbrock manual the VE(Volumetric Efficiency) of a stock engine with stock manifold is somewhere between 60%(.60) and 85%(.85).

I believe your 63 has a 401 CID motor..Let's assume a max operating RPM of 5500rpm and a VE of 100%(1.00). it should be like this.

401 x 5500 x 1.00 divided by 3456 =638cfm.

Using these figures a 650cfm carb would be fine.However your VE will be lower than 100% so the computation is more for illustration purposes.

Also a carb with vacuum secondaries generally get better milage than one with mechanical secondaries.With vacuum secondaries the carb is more "on demand"..Mechanicals can open when it's really not needed.

Posted

600 cfm is a perfect match to the 63 Nailhead 401. The response mentioning 100 per cent VE is nice, but a typical internal combustion engine is much lower then that. If you go too high, then there are problems. You can't just assume that you can add more power by putting a monster cfm carb on any old engine. The engineers matched the demands of the engine to the size of the carberators, once carb technology took off in the mid fifties.

Now the obvious choice for transmission to me if you want to ditch the Dynaflow, is the TH400 or the TH350. I, and several others on this forum, have owned 64 Rivieras and they have the early TH400 (whatever Buick called it) and they were bulletproof, smooth transmissions.

The TH350 ought to have the same mounting holes and offers less weight, so it would get slightly better gas mileage. I have heard the TH400 takes 10 per cent more "energy" to operate it but it's heavy duty.

As for conversion, you would need probably a different flywheel from 64-66. I can't answer to the starter location issue. Get under your car and look, either on a hoist or lifted up and see if there is room or mouting holes on the other side.

Posted

There was a 63 Riv at the ROA nationals in Eureka Springs in 2005 that was driven in from North Carolina. The owner had done a 700R4 conversion and said he averaged around 22 mpg for the 1200+ miles he drove it. He reported no problems and excellent drivability. I'd contact a reputable transmission shop and see what they have to say. The conversion pieces should have nothing to do with the operation of the transmission; they're just hard parts that mate the two together. What you're describing sounds like a typical transmission problem. Perhaps the TV cable needs adjustment????

Ed

Guest 63riviera
Posted

Well, I had Bob Bendtsen's Transmission (the guy who makes adapters for nailheads with a dynaflow to mate up to more modern transmissions)test drive it today when I brought it back.

After I got it, it seems the engine has to reach a high rpm just to get moving. And that in gear it seems to search for gears when accelerating.

Well, I had Bob test drive the car today,and he thinks it's normal. For me (who's had the car since '83), it "feels" like more slipping than the leaking dynaflow he replaced. After talking about rpms, he hooked up a tachometer while we were test driving it. The tach read around 2200rpms at 15 mph. He then said he put a 2000+rpm stall converter in it,because most people want that. Shifts did occur around 2200+rpms. Yet, for me to get going from a dead stand still, it's like there's very little positive engagement. When he was driving it, he had the throttle almost to the floor. He then said there could be fuel starvation (not true the engine runs great), and what I'm hearing is the flex-fan ( yes, I know this makes more noise than a clutch fan; the flex-fan has been in there since '92, and I know how the engine sounds under all kind of conditions. I also have a '73 Riviera GS stage 1 with a flex fan and a '76 Riviera with a clutch-fan. With both of those cars, there's a positive engine to transmission engagement, smooth shifting and in the '73, there is a flex-fan roar that I'm fully aware of and distinctly different than feeling the engine sspeed (rpms).

I know the '63 thoroughly--- how it responds, the engine, the old transmission. I've had it since '83.

We agreed that he would have a different stall converter (~1500 rpms).

Has anyone else had experiences with Nailheads and 700R4 transmissions?

Oh, and Tim63Riviera, I'm in Minneapolis.

Guest 63riviera
Posted

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Hi

I also have an 63 Riviera, and i am not really happy with the dynaflow. I think a 350 or even 700 would be a better choice and i also plan to change it, however i am from austria and here its much more difficult and expensive to do this.

how do you fix the problem with the starter? it on the left side isn´t it? and all other transmissions have the starter on the right side. and please keep me up to date, so i will not make the same failure like you. Furthermore i will make myself a christmas present and get a new carburator (Edelbrock) and i don´t really know if its better a 600 or a 750. On buickstreet.com they suggest a 750, but all in other forums they suggest just an 600. so the question is, if an 750 brings that much power, and therefore it is worth paying 20% more for gas or not. In europe petrol is way more expensive than in the US,(around 1,1?.-/L)(i don´t know how many gallons that would be) so for me this choice is quite important.

greetings from austria

Alex </div></div>

for me the conversion was ~$3250 for a rebuilt 700R4. Bob did A LOT of work--shortening the driveline, adding a new cross-member, his special trans adapter, an electronic controller.He said there many problems doing this conversion.He is the specialist who just deals with this area, so I did trust him. Now my power steering gearbox, I had rebuilt in CA is leaking. It wasn't this way before.

And after this conversion was over, I have worse trans performance than the old dynaflow.

Someone emailed me, saying it could be the torque converter. That seems a likely place to start. Bob said he would put a lower rpm stall converter in in.

So,we'll see what happens

Posted

Hey, we're almost neighbors!

I don't know why Bendtsen would put a higher than stock stall converter in a Nailhead equipped Riv unless the owner asked for it specifically! High stall converters are usually used with engines that don't make good torque at lower RPM's which ain't the Nailhead! I think you'll be much happier with a stock stall speed converter, and Bendtsen can sell the old converter out of your Riv to the next SBC pilot who walks through the door!

Good Luck!

Tim <img src="http://forums.aaca.org/images/graemlins/smile.gif" alt="" />

Guest 63riviera
Posted

Tim, have you had any experience with Bob?

Today, when I brought back the car, his attitude was a bit, well... antagonistic. I mean he acted like I have no experience with this car. Although i haven't done all the work on the car( like the paint, body work, machining of engine parts), I have done most of it, since I've owned in '83; and like i do on my other Rivieras--a '73 GS stage1 and a '76 with a '70 stage 1 engine in it.

It wasn't just the rpms at the shift points, but the TIME it took to get, say from 0-30 mph. It actually felt dangerous driving out on city streets, because i felt I couldn't accelerate or start moving even adequately. And then way he was driving the car with me in it--- he was driving like a it was junkyard derby contest!! I felt like saying, "Hey, this is my 44 year-old car; have some respect." There's some original red 300C--the first one--on front that I think is his. I would NEVER drive that car the way he was joyriding in mine. And then after flooring it and jerking it to a stop and jabbing the accelerator, he said , "See?? It just stalled because it has a fuel starvation issue." BS!! I drove that car from CA to MN, after replacing the fuel pump and all lines, and the engine ran great (with an all-electronic ignition). Yeah, the carb had some choke problems, but after running it for a couple of minutes, it runs great.

And then my new power steering lines/ gear box-- which were some of the last things that were done before it was stored; It never leaked in storage--not a drop on the floor. Today when I drove it there, I heard the power steering pump squeal, and looked on the floor, and saw a huge pile of steering fluid; the reservoir was nearly empty. When I picked up the car, he said he had problems--making a new crossmember and that my power steering lines/box was leaking. I wonder why... That new crossmember is near the gear box

I'm sure he takes pride in his work and is excellent at what he does (or so i assume). But in terms of communication with customers, he has a lot to learn

Posted

'63 Riviera, if you want a lower stall converter with a tight feel, you may want to go with a 1994-1996 stock LT1 torque converter. These were on the Chevrolet Impala, Buick Roadmaster and Cadillac Fleetwood, are readily available everywhere, stall at about 1477 rpm, and have a high STR rating. The STR rating is what determines how loose the converter feels.

Just run that suggestion by your trans builder. The 700R4 is mechanically identical to the 4L60, except that the 4L60 is electronically controlled. If I remember correctly, their converters are interchangeable though.

The higher stall/loose converters are used by drag racers, who can get off the line at a higher rpm and enter the powerband quicker. It makes it annoying around town though.

Good luck!

Posted

Hi,

Yes, I have had a mixed bag of experiences with Bob. First time I met him was in his booth at Back to the 50's in 2003, right after I bought my Blue 63 Riv. I looked at the display, asked him some questions about the kit and all was well. Then I asked him about some of the particulars of using his Nailhead kit on a 63 Riv, and "BANG" the guy goes off on about how he just makes the adapters, it is up to you to figure out how to mount it in your car. A small group had gathered when we had been talkng earlier and most of them just stood there dumbfounded when he started his rant! Then just as soon as it started, he was done and actually started to answer some of my questions! I think he is a talented fellow who needs a good Sales and PR person to deal with the public and he needs to stay in the back room and work on the technical end of things. We hashed this out over on V8Buick a couple of years ago and I was amazed at the number of well respected Buick people that had the same type of interaction with Bob. Good quality products backed up with rotten customer service!

Tim

Posted

There are a couple of things you might want to consider if you want to change a dynaflow to a later modle trans. You can change to a 64 - 66 Buick trans, their ST400 (Buick's name for the Turbo Hydrod TH400) and it will bolt to your block. You would need to do some machine work to the crankshaft or get a hub adapter, the proper flex plate. Dynaflows have the starter ring on the converter, all others have it on the flexplate. You'll also have to swap out your shifter, the sequences are different. Dynaflow are PNDLR, and the ST400 and all others are PRND2L. The dynaflow uses a mechanical kickdown for passing gear, the ST400 uses an electric solenoid.

What is it that you don't like about your Dynaflow. It is the classic cruising transmission. Never in the wrong gear and no bothersome shifts to worry about. I love mine. The only drawback is that it is not as mechanically effecient as a later model.

Ed

  • 3 weeks later...
Guest 63riviera
Posted

I did like the dynaflow for 20 years. but when it started leaking again, and parts were hard to find, I thought going with this 700R4 transmission would be a good upgrade.

I wish I had found someone to rebuild the dynaflow, because this 700R4 is still not working the way it should be.

Bendtsen did put a lower stall converter in it, but it still feels like there's very little firm engagement from the engine to the transmission. Going from 0-30mph takes forever.

I had wanted a THM-400 with switch pitch, but bendtsen insisted on the 700R4. In my other Rivieras with a THM-400, shifting is smooth, firm and "engaging".

This guy is impossible to deal with. He's extremely argumentative whenever I ask any question.

I actually had better performance from my slipping, leaking dynaflow.

So, yeah, I did like the dynaflow, and wish I still had it.

Posted

Why dont you get another opinion... Give Greg a call at Phoenix transmissions and tell him what is going on. See if he has a suggestion for you. Then you can go back and "discuss" it. He is at 817-599-7680.

Web site is http://www.phoenixtransmissionproducts.com

Very knowledgable in both the early and later trannys.

BTW, did you get to keep your dynaflow or was that part of the transaction ?

Posted

Steve,

Does it seem like the transmission is shifting into all four gears? If it is doing a second gear start, that could explain the feeling of slipping and also account for the length of time to reach 30 MPH. Is your shifter set up to be able to achieve manual 1st gear? You could pull it into manual 1st gear and then move through the gears manually to see if that helps acceleration. The 1st gear ratio in all 700's and 4L60's is 3.06:1 which should really pull strong behind a Nailhead if everything is OK. I would be willing to look at it for you when the weather warms up in a couple of weeks!

Take Care,

Tim McCluskey

ROA 9686

Guest 63riviera
Posted

Thanks, Tim.

I'd appreciate that anytime.

my # is 760-989-1597

Guest 63riviera
Posted

I had hoped it would, too.

When I picked it up, Bob claimed the problems were due to the carburetor, which worked great with the dynaflow. It looks like he's added some cable to the kick-down tab, where the mechanical linage used to activate the S/P dynaflow. he also has an electronic controller, which he wired by sticking its 12V wire into the fuse box on another cicuit. Being a big high-end mobile audio buff, I spend time on wiring--fusing each lead within 18" of the battery, neatly running and organizing wires, etc. In Bendtsens web page, he exalts every piece he makes, like this electronic controller, calling the very best one on the market, yet he wires it like a hack stereo installer.

Since It's now sub-zero here in MN, with a lot of salty road, I'm not planning on driving it for awhile.

Tim,I think I will try the manual 1st gear shifting.

But I just cringe driving it, trying to get to 30mph is such a slow endeavor, it makes me ashamed to drive it. He claims this is a rebuilt transmission; it performs like it needs rebuilding!

This 700R4 project was a big mistake. I wish I could have used a '65 TH400 with S/P. I love the THM-400's in my '73 GS and my '76. GREAT TRANSMISSION!!! Firm engagement, smooth shifting at the right times. Some have called the THM-400 one of the world's best automatic (Rolls Royce uses it), and I can see why.

My disappointment with this major,expensive conversion is really troubles me.

I love my '63, and when he was test-driving it with mein the car, he treated the car like crap. mashing the accelerator, slamming on the brakes, arguing the whole while how "this is normal."

One thing I learned about working on my riv's: If you don't do it yourself, most of the time the work won't be done right (well, I've had a couple of good mechanics--but that isn't the rule).

Posted

I pasted and copied this after Googling in TV Cable 200R4. From all the literature I've collected and the trans people I've talked to I understand that if the TV cable is not connected correctly one of the first things that will happen is that you'll burn up your trans - big time, "Like replace the whole trans, Dude."

Here's a portion of what I pasted and copied.

"Chances are good that everyone reading this has either done it or knows someone that has installed a 700R4 or 200R4 into an older car or truck and has not been happy with the way it shifts. The most common complaints are that it shifts too hard, shifts too late, or won't downshift more than one gear. In a lot of cases, they were told to back the cable off to soften the shift, but then they would lose the multiple-gear downshift and cause the trans' pressures to drop--resulting in shortened trans life.

All these problems are the result of the TV cable not being set up properly. We cannot stress enough the importance of the relationship between the carburetor and the TV cable. Just simply bolting on a bracket that holds the cable is not enough."

If I were you, I'd not drive the car until I had the correct parts in place and set up by someone who really knows what they're doing - seriously. Get on the internet and read everything you can about how a 200R4 operates from the pressure applied by the TV cable. There are aftermarket parts available to make sure that you get everything synchronized and working properly. IT's an art to get the tension of the TV cable adjusted properly. If you need some leads on carb adapters, base plates that go between the carb and the manifold to hold the cable properly, let me know and I'll send you some links I have stored.

I'd have written this a long time ago but I figured that Bob knew what he was doing, perhaps not!!!!

Ed

Posted

Ed-I run the 200 trans in a turbo car myself and know that the TV adjustment is very important with this trans. I'm not too sure the 700 is the same deal tho. Tim will know and BTW, I'm in the Twin Cities, too. I have a '66 Riv and agree that it's hard to beat a 400.

  • 2 weeks later...
Guest 63riviera
Posted

Rivnut, I thin you're right--it is probably a carb> trans TV cable adjustment. At first, he said that he encounter problems doing this conversion. He mentioned how my original Carter AFB was the problem. First he claimed the choke was too lean--which it wasn't; it always ran rich (there's not even a thermostatic oil in the choke). But with the dynaflow, the carb ran well and very smoothly.

I finally did pick it up after he changed the stall converter. He now claims there's nothing wrong with the carb.

he stuck some TV cable bracket to the back of the carb's rear intake mounting bolt. I and my friend asked him about adjustments that may have to be made. When I first picked it up, he insisted the trans was working exactly the way it should. And also what I perceived as high rpms is just my "roaring" flex-fan; I am intimately familiar with how this fan has sounded; it's been that way for 20 years. Than after I last picked it up, he contradicts himself saying the trans was working MUCH better.

well, it doesn't. It would be apparent to anyone driving the car. There's definitely some adjustments that need to be made with the carb, but it IS impossible to deal with him. There's always some rationalization. I even asked him about the kick-down cable to the carb, and if it needed to be adjusted. I don't think I ever got an answer to that question.

I really haven't had time to deal with my '63; I've been working on the '73, and been busy in my own personal life.

But it bugs me, after paying all this money, that even the leaking dynaflow worked better than this arrangement. I really wish I had never had this done.

Posted

Hang in there. There are too many good swaps out there to think that this shouldn't work for you. Get your 73 going and in your down time read as much as possible on the 700r4 and the 200r4 and how they work. Your trans shouldn't work any differently than any GM product that used it as an OEM application. Thanks for the warning about the service. I guess for me its "buy the product, leave the swap to someone else."

Ed

Posted

This whole thing sounds like the simple conversion that went WRONG in a handbasket, unfortunately. With the deep low gear of the THM700-R4/4L60 "analog" transmission (4L60E is the electronic-controlled version), the low speed performance should have increased greatly over the DynaFlow . . . I would have suspected.

I tend to agree that the throttle cable (i.e., "detent cable") adjustment might be an issue. In looking around at RockAuto.com, I looked for various Chevrolet applications which used the THM700 transmission to see about cable lengths. I found cable lenghts of about 44"-48" and then the 350 TunedPortInjection motors had one listed that was 61" long. Also, a universal cable that could be anywhere from 28"-48", depending upon various factors and you also had to make the "carb end" attachment for your application. Somewhere in that mix of lengths, I suspect there might be something that would work with a non-OEM production THM700/Nailhead combination.

In stock form, the THM700 is a very smoooth shifting transmission, with the later models rivaling the THM400s in that respect . . . especially considering the huge gap between the 3.06 low gear and the 1.72 2nd gear.

When we got one of our first pickups in with the THM700 in it, when that transmission was new, the transmission had a problem which required a rebuild. The transmission tech rebuilt it (with little information from GM, at that time, which was the initial production run of them in C-10 pickups. When he got it put back together, test drove it, and it still was not acting right. He pulled it back down and found nothing out of the ordinary or something that might have broken after he put things back together. Still, it didn't shift right (or as expected), which seemed to be a detent cable adjustment issue.

Using "conventional knowledge", he put more preload into the cable adjustment and made things worse. When he adjusted it "backward", then things improved so he did it some more and then things started acting right. He later confirmed that rather than put preload into the cable to get it to raise shift points and such, you took preload out of the situation. I remember that deal speficically as it was "different".

On the issue of detent cables, there are different ways to mount the cables to the engine/carb. There is one GM bracket that goes across the rear two bolts of the carb (Q-Jet in this case, a "spreadbore") and had the throttle cable running on the top of it and the detent cable attaching right under it in the bracket. You can also find brackets on the Edelbrock and Holley carb websites, under "accesories" or "mounting hardware". There are also some "mongo" brackets available from other sources too, which seem highly over-engineered for what they are supposed to do . . . and more expensive. The THM350 uses some similar brackets, but the one normally used is one that attached to the rear two intake manifold bolts on the driver's side of the engine (as in the small block Chevy side of things) and carries a GM part number ending in "000", as I recall.

I also seem to recall some of the detent cables were "self-adjusting" in configuration. There was a metal plate that you depressed to effect this adjustment feature, with the carb at WOT--which might have been for the THM200 family . . . it's been a while. In any event, with an OEM application, it was no big deal to change the detent cable and get it adjusted for things to work right.

Other detent cables adjusted by turning the mounting block (which you snapped into the carb bracket) on the plastic cable housing. They didn't look like they'd adjust, but there were faint threads on the cable housing and the block did turn on it.

I suspect that when you might bird-dog an OEM application for the THM700 as to the detent cable mounting and adjustment, you might see if you can replicate it on your Riv. For general principles, you might get some 3/8" rope and duplicate the routing from the carb to the trans case where the cable is retained down there. Then you can possibly compare your "rope" measurement with an OEM application of a THM700 transmission (some of which I listed above). I suspect that when you might get a cable that is closer to an OEM application, the adjustment issues might be easier to make happen and duplicate the OEM adjustment situation.

The THM700/4L60 transmission is the "darling" of the street rod/street machine crowd, in slightly modified or in higher modifided configurations. There's no reason it should not be so difficult to make it work in any application it was not originally in from a GM factory.

If the transmission you got needed an electronic controller, I would be interested to find out what it "controls". GM Performance Parts does have stand-alone transmission controllers (computers) for their electronic-controlled transmissions, but the "analog" transmissions do not need them.

On the transmissions that used an electronic instrument cluster, they substituted a "tone wheel and sensor" in the same hole (on the tailshaft housing) and the tone wheel went onto the output shaft where the speedometer drive gear went, so that the change from "normal" speedometer gears to the electronic speedometers in the electronic instrument clusters was an easy swap-out situation.

One advantage that the THM200 transmission family would have is decreased power consumption, when compared to the THM400. The THM200 has a 2.74 low gear and a 1.74 2nd gear, so that's not that much different from the THM700, but the THM700 family is a stronger transmission family. In either case, the "low gear launch" should be significantly better than a DynaFlow.

As for the stall speed issue, stall speed is directly related to the power of the engine in front of it. A converter that would stall at 1600 rpm behind a normal 200 horsepower V-8 would stall at a higher rpm when it was behind a 350 horsepower V-8 . . . and vice versa. Yet, the performance converter industry still talks about "stall speed" as a generic term in their advertising, typically. With a lock-up converter (as the THM700 has), after particular engine vacuum and vehicle speed/gear criteria are met, the converter locks up and the stall speed issues which might be an issue with a higher stall speed non-lockup converter at cruise are not there. I also suspect that unless you were attuned to such things, you might not really be able to tell the difference in a 1600rpm stall converter or a 2000rpm stall speed converter behind the same engine. Now, if the stall speed on the converter was 3000rpm, then you'd notice a difference in how much rpm it took to move the car from a rest with modest throttle input.

IF he put a 2000 rpm stall speed converter (in a small block Chevy realm of things), it might be a little too loose when its behind a Buick Nailhead V-8 of about 401+ cid . . . but it all goes back to the engine's power that made the small block Chevy 2000 rpm stall speed converter stall at that particular rpm range. Or it might be more "dead on" than we might suspect. Highly variable!

On the issue of the large amount of throttle to get the car moving and the engine noise issues, I recall reading in a Ford C6 trouble-shooting chart (in my 1966 MOTOR manual), that higher engine speeds for given road speeds could be related to a defective part in the torque converter (staying in "reduction" mode all of the time) as the cause of that . . . plus poor acceleration. It also tends to sound like there's also some sort of "shift kit" in the transmission too . . . just my gut suspicion. There could also be a valve body issue, letting pressure go to two areas at the same time rather than where it needs to go (similar in concept to a "trans brake" applying a forward gear and reverse at the same time).

From what I've read, this whole deal sounds like everything that could go wrong, did, unfortunately. It might not be possible to get "satisfaction" from the installer or get him to admit to what the real issue might be . . . or for him to admit to some issues with another operative who might have supplied him the transmission, which he resold to you. Many "unknowns" which might never be revealed or resolved.

As you've found out, not everybody does the same quality of work that you might do yourself, provided you have the expertise or time or tools or shop space to make happen. It might be best to get the detent cable issues tackled first. Then possibly look at the shifting issues (timing and quality) which might still be there.

I'm not sure how the power steering leak might figure into the conversion, but I've found that when I've bought a used car and the power steering fluid was "red", it meant there was automatic transmission fluid in it. ATF and PSF might be of similar viscosities, but they have different functions and the fluids are configured accordingly. When I managed to get the ATF out of the systems, replacing it with genuine GM (or Chrysler) power steering fluid, the leaks/seeps stopped. The systems I've had which I always kept power steering fluid in seldom had any leaks or similar issues, until a hose deteriorated with age and started to fail.

The comment about the shifter needing some changes to reflect the new multitude of transmission gears now available might be something to work on too. There are detents in the shifter (even on the steering column, internal to it) as there are similar detents on the linkage inside the transmission. Determining how the installed handled that might be interesting to find out.

I feel certain that when the "adaptation issues" are finally worked out, you'll really enjoy driving the car. When Phoenix Transmission (which Bill Stoneberg mentioned) did a swap of a THM400 into a '62 LeSabre for the existing DynaFlow, the performance potential of the Nailhead V-8 was suddenly increased enough that our chapter member had to keep his teenage son out of the car (Dad was having too much fun, it seemed! . . . plus knowing his son's driving habits too). When I was asking Greg (at Phoenix) about the swap, he started rattling off the specific salvage yard parts he'd need and that they were usually available locally. As Stoneberg mentioned, Greg's highly knowledgeable in all things "automatic transmission" and they have been supplying THM700-R4s to the street rod customers for years.

I hope you can get all of the things sorted out to your satisfaction.

Just some thoughts,

NTX5467

Posted

Here's a website that you should check out for help in properly selecting and adjusting the TV cable on your transmission. www.tvmadeez.com

See if you don't agree with me that what they offer won't make your installation that much easier.

Posted

$3250 for a rebuilt 700R4... heck, you can buy a running, going 67-71 Jeep Wagoneer with a TH400 that bolts to the nailhead for like a grand.. a 64-66 Buick flexplate with the center hole enlarged and a GM short tail 400 tail cover and you're in business. And you can sell the Jeep afterwards to a Jeep guy -

Posted

HI all, just some thoughts:

$3250 was for the transmission, adapter and installation.

I would imagine that the electronic controller is for the torque converter clutch operation, not shifting.

The T.V. cable on a 700 or 4L60 controls line pressure and shift feel. Upshifting and downshifting are still controlled by the governor. The way it sounds, this car has either an issue with the torque converter or is making a second gear start.

I used to think that the Jeep THM 400 bolts up to the Nailhead, but after a salvage yard visit, I'm not sure. The Jeep bellhousing is shaped very similarly, but it looks to be deeper than the Nailhead THM 400. Has anyone done this swap and do you have pictures?

Thanks,

Tim

Posted

GM sold the nailhead pattern TH400 as a universal-pattern trans to Jeep and several other carmakers in the late 1960s. The shorter bell on the case made it much easier to cast adapters to bolt to other motors (a-la the case design of the 1956-up dual coupling Hydramatic), including in some Jeeps an adapter to bolt it to a Buick 350 with standard BOP pattern. A guy on the HAMB posted the information there; we have a junk '69-ish Jeep with the trans I plan to rip out when it gets warmer and match up to a '58 364 -

Posted

Hi Pontiac59,

There are currently both a Nailhead bellhousing THM 400 and a AMC bellhousing THM 400 over on ebay. Like I said, they look somewhat similar, but do be aware that there is an AMC case THM 400, and it won't fit on the back of a nailhead. Do you have pictures of the "universal" Nailhead bellhousing with the AMC adapter plate? I would really like to see it!

Thanks,

Tim

Posted

On GM's non-electronic control automatic transmissions, torque converter lock-up activities are controlled by a vacuum switch (low vacuum unlocks the converter and I seem to recall a "high vacuum" switch to unlock it during closed throttle coast-down situations), which are in the converter clutch circuit prior to the brake light switch. For example, if the vehicle is on the straight and level road at sufficient speed to allow converter lockup to happen, when an incline is encountered that results (with the cruise control on, for example, to maintain a set cruising speed on the highway) in additional engine load and decreased manifold vacuum, the converter will unlock. If that does not decrease the engine's load enough, then a downshift into "D" (direct, or high gear) will result. When the load decreased on the other side of the incline, the trans will again upshift into "OD" and the vacuum switchs will let the converter lockup or whatever they let it do. The low vacuum switch also makes sure the converter is unlocked at WOT in OD (although a few valve bodies would keep the converter locked-up at WOT . . . Corvettes, Z-28s, genuine COPO police Impalas, diesel pickups).

While at a steady speed with the converter locked-up, a slight movement of the brake pedal (to turn on the stop light circuit, usually) will result in the converter unlocking until the brake pedal is released back to normal.

In other words, the circuit has to be "made" in all cases for the converter lockup solenoid to be energized and lock-up the converter electrically. Everything is "analog" rather than "computerized", in these non-electronic controlled transmissions. When the "E" was added to their nomanclature, they got electric solenoids inside the transmission, on the valve body, to make things happen in there. Still, some extra sensors and such, but everything was controlled by the ECM. On the crate transmissions that GM sells with electronic controls, there is a separate controller to run them.

Seems to be some mysteries on how this whole deal might work!

Just some thoughts,

NTX5467

Posted

NTX5467,

I do remember some of the GM Diesel's using a vacuum switch on the pump to regulate vacuum for things like EGR and other emission related items. Some early 80's vintage 350C, 250C and 200C used with non-ECM controlled engines used systems similar to what you described. All of the THM 700's use an electrical solenoid inside of the transmission case on the pump to control lock up. By the time the 700 came on line in 1982, all car and a good number of truck engines were ECM controlled, so it just made sense to give the ECM command of the TCC as it already knew things like engine RPM, throtle angle, vehicle speed and engine load. Along with the ECM, there was a brake switch wired in series with the TCC solenoid, so that any time the brake was applied, the electrical circuit to the TCC solenoid was opened up, unlocking the converter. There are also pressure switches inside of the transmission pan on the valve body that monitor clutch apply passages. The 700 uses 2nd gear oil pressure to activate the TCC regulated apply valve, so even if there is an electrical failure, the TCC will hydralically disengage when the transmission makes the 2-1 downshift. There was a pressure switch that was contolled by clutch pressure to the 3-4 clutch; that switch had to be closed for the TCC solenoid to receive voltage so the TCC would not apply in 2nd gear. The THM 125C (3T40) used line pressure for TCC apply; a TCC solenoid failure could cause the engine to stall if the TCC remained engaged when the vehicle came to a stop. Very bad design! Some of this stuff was so long ago I'm really dating myself to admit that I worked on them when they were new!

Take Care,

Tim

Posted

Tim, when I did my comments, I'd forgotten about the pressure switches on the valve body that were the "first" switch to close in the circuit to let the converter clutch lock-up. In the earlier years, converter clutch lockup was set at a low mph, but by changing the switches on the valve body, the lockup speed could be raised enough that it didn't cause any real issues for the customers. There were lots of vehicles out there with "a skip at 45mph" that a tune-up or anything else could not fix . . . except a pressure switch with a higher rating. The "outside" transmission shops usually had a selection of pressure switches in stock.

Depending upon which vehicle/engine combination the transmission went behind could determine how and when the converter clutch lockup circuit would "make". In most of them, the converter clutch would not lockup until the trans got into 3rd or OD, but there were some Buick application THM350s that would lockup the converter upon the 1-2 upshift. Most of what I was involved with back then was on the Chevrolet side of things, but there were also Buicks in the mix too.

I also recall selling many of the TCC solenoids for the THM125s. That was an easy diagnosis and fix (like some of the other "common" problems on GM vehicles in that general timeframe). Not terribly expensive to fix, either, compared to some other things.

The vacuum switch on the Stanadyne diesel pumps was to vary vacuum to the transmission's vacuum modulator valve, which modulated vacuum generated by the vacuum pump that went in the same place as a distributor would on a gasoline motor, in the engine block. The same vacuum source was also used for other things on the vehicle (i.e., hvac vac-operated valves, EGR vac). At least for transmissions that had a vac modulator valve in the first place.

In that same timeframe, the Olds 307 (5.0L) V-8 also had a belt-driven vacuum pump that was a "booster pump" to run the hvac items and probably other things. Remember that this was also during the time of the famous "PowerMaster" brake booster? A good design, in concept, but was a little too "different" for many people and mechanics to deal with--one of the first power assist units that didn't require engine power to run directly, if that matters.

Enjoy!

NTX5467

Posted

NTX5467,

I was at Olds and Cadillac dealers in the 80's and ran accross many of the same things. The 307 Olds engine seemed to only have the belt driven vacuum pump if it was equipped with the THM 2004R, 350C and 200C transmission equipped 307 didn't get them. I don't think Cadillac and Olds did use the 350C behind the 5.7 diesel, they used 200's, 200C's and then 2004R's so there was no vacuum modulator to deal with. You Chevy guys got some 250C's or 350C's in the 1/2 ton pick ups with the diesel, although I think that the early pick ups (1979?)were limited to the 200! It is amazing to watch the transmission technology changes in Hydramatic today when you look back on some of the early TCC systems and Over Drive transmission attempts. Boy, talk about hi-jacking some elses post!

Take Care,

Tim

  • 3 years later...
Guest RivieraBear
Posted

This is an old thread, but personally, I like the 63 BECAUSE of the Dynaflow. It's way cool. If you don't like it, I guess you could get a 64 or 65....

Posted

It sounds like the stall converter is to high of an rpm rating. (stall speed) If memory serves me, most factory torque converter stall speeds are around 1400 rpm. Who is "everybody" that wants the torque converter that he thought was appropriate and what kind of cars do they drive. If they are hot rods with hot cams, then you got the wrong converter for a stock Riv.

  • 4 months later...
Guest sergvillarreal
Posted

By the way, for those of you who did the 700R4 conversion, what shifter/cable combination did you use? Does it allow you to retain the console? I am considering installing a Lokar shifter, but worry about the interference with the cable...

Guest 40series
Posted

Ue a stock 65 shifter with amodified rod and go with a stage1 200 4R transmission. I have done the conversion twice now and it is a nice fit as well as function.

Use the EELCO adapter for a cleaner install. (shameless plug :))

Posted (edited)

For the 200-4R conversion that I'm working on for my '64, I'm using a shifter from an '84 Monte Carlo SS. The SS came from the factory with the 200-4R. The diameter of both the OE Riviera shifter and the Monte Carlo shifter are the same diameter. They both incorporate a "push to release" mechanism for the reverse lock-out. Some simple modifications to the shifter rod and you can put the Monte Carlo shifter inside the Riv's console. The nice thing about it is that it's a cable shifter and the geometry is correct for having the trans in gear with the shifter lever in the proper location on the quadrant. The only thing that's necessary to modify is the neutral safety switch.

Ed

PS - I'm using one of Eelco's adapters. An article I wrote on this swap was published in the Riview last year. In it, I explain why I (along with others) chose the 200-4R over the 700-R4. There are a number of pictures of the installation as was done by Dave Gee on his '65.

Edited by RivNut (see edit history)

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