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Discussion Starter #1
I've got a 4bt mated to a 700r4 in my 71 chevy 4x4. It's been in there over 1000miles now. I did not use any adapter at all. I used 2 methods. Here's how it was done:

method 1. I used a 4" angle grinder and slotted every other bolt hole on the "ribbon adapter" to the inside.(the bolt pattern on standard 700r4 is 3 bolts at 10.75" and the ribbon is 6bolts at 11.5"). I then got some longer grade 8 bolts torque converter and used 1/8" hardened wahers between the ribbon adapter and the TC, lock washers behind the ribbon, and red loctite. It didn't work loose in 1000 Miles.
However I was a bit concerned about vibration(bolts and slots not balanced) and the possiblity of the TC not being centered properly as the tC doesn't engage the snout in the center of the crank.

Method 2. After being told by another guy that the 1/4" gap was not too much you could just pull the TC forward up to the ribbon and it would work fine. I took the bolts and washers out and used 3 stock bolts and just bolted the TC to the slotted ribbon mount. It works no problem. No leaking fluid. TC works fine. Tranny is working fine. My vibrations also decreased a little bit.


So after all this I beleive that to mount a 700r4 to a 4bt all you need is a $10 harbour freight angle grinder and 10 min to slot every other bolt hole to the inside and then bolt it up with loctite. No adapter ring necessary.

Now I've seen some of the ring adapters. They look nice. I have no doubt they are better. I have no doubt they make you feel better. The question is "is it necessary?". I don't beleive it is.

As far as the 700r4 living behind the 4bt I would say that if your tires aren't bigger than 33 and your 4bt torque figures are not more than a vortech 350 and you don't tow in OD you should be OK. If you have a manual lockup switch to lock it up in 3rd gear when towing to prevent heating up the fluid it will be even better.

Alot of guys spend alot of money on heavy duty parts and things they really don't need. It makes them feel good and maybe that's worth the money for them. If you tell guys that their swap will self destruct when you don't really know will keep inexperienced guys with a small budget from trying the swap.
 

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So after all this I beleive that to mount a 700r4 to a 4bt all you need is a $10 harbour freight angle grinder and 10 min to slot every other bolt hole to the inside and then bolt it up with loctite. No adapter ring necessary.
And it's still going to be slightly out of balance. Why add vibration to something that already rattles & shakes notoriously?
 

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Well, I'm going to go out on a limb here and wish you luck, because I think you might need it.

Not going to say that it won't work, but it seems like a really bad idea. I've wondered about the durability of that little band in it's stock form, and there is no way I'd do anything to weaken it.

Finding an easier way is something we all look at from time to time, but please don't think that since it lasted for a thousand miles that it's a good idea. I'm more than a little irritated that you offer this up as an alternative to doing it right, and then kind of insinuating that every one who does his homework, and does it right is just doing it for a warm fuzzy, and pitching money away. You now have an elongated hole where cracks can form, you have given up approximately a third of the clamping area (which, as near as I can tell, is the greater part of the strength in that assy.)

Like I said, I wish you luck with it, but if I were you, I'd start gathering the parts to fix it, now, because chances are, it'll let you down in the long run.

Doug
 

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Discussion Starter #5
Ok, I don't assume my way is the "right way". I mean to say that the adapter ring is not "the only way". I did say "I have no doubt they are better."
I don't mean to insult anyones good work. I just want people to know that you can bolt it up and it will work. I seem to be the first person on this forum who just bolted it up the cheap way and wrote about it. While lots of people have been asking how to do it.
I have no doubt you are right on the vibration issue. How much vibration you introduce depends on how good you are with the grinder. To some guys it doesn't really matter. As far as stress cracks on the ribbon...It is steel. It is not subject to rapidly changing stress(like a connecting rod pushing and pulling). Steel does not tend to crack and shatter as bad as aluminum. We will see what happens on this. I got this technique from another guy who did this and has 52" tires and much more stress than I ever will. He slotted his ribbon with a cutting torch which also affects the heat treating of the ribbon. He has no problems yet.
Working on cars is a hobby for me. I'm not rich. I do all my own work. When I can I come up with my own solution before buying someones kit. The original hotrodders did it all themselves. I've seen engines dissassembled and rebuilt on a piece of cardboard in the dirt driveway over a case of beer. There is a time and a place for everything. Too many wealthy car enthusiasts will lead the new guys to think that if you don't have the latest carbon fiber reinforced balanced and blueprinted billet titanium CNC machined in a hermaticly sealed QC inspected work environment that their engine will catostrophicly fail at any moment probably killing everyone within the blast radius. I just get tired of seeing young guys that don't have enough money already thinking they need things they don't. This is a fun hobby. We need all types here.
 

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If you tell guys that their swap will self destruct when you don't really know will keep inexperienced guys with a small budget from trying the swap.
Personally, when someone asks me a question about anything that I don't really know about I tell them that I don't really know, and can't tell them for sure what the answer to their question is. But that's just me.

Now I know that you did not ask, but I am going to offer you an educated guess as to what is going on inside your torque converter and transmission right now, and what I am speculating the resultant damage to be. If I understand your description correctly, the only mechanical connection between your engine and your torque converter is three bolts fastening the 'wave ring' to the lugs on the converter, and the snout of the converter is not coupled to, inserted in, or otherwise properly lined up with the back of the crankshaft. If this really is the case, (and right here is where I gotta say HOLY SHIT!! :eek: ) then it is it is my speculation that you are destroying the converter clutch and front pump bushings, and are probably going to crack the snout of the converter where it is welded on. You will probably also ruin the front pump, partially from the converter snout wallowing around (will wear/break the drive tangs on the pump gear) and/or partially from all the fine pieces of metal that will get pumped through it from the bushings and the converter clutch. Additionally, you stand the chance of ruining the input shaft/front drum assembly as well. Have you checked your transmission fluid in the last 1000 miles since you started running this way? Please take the dipstick out of the tranny and wipe it on a clean white rag, then look at the fluid in bright light and tell me you don't see what looks like a dark metallic red paint.

On the upside, all of the money that you saved by not purchasing an adapter can now be used to rebuild/replace your tranny and converter when they go bad. Oh, and to purchase an adapter, too. :rasta:


Like I said, I wish you luck with it, but if I were you, I'd start gathering the parts to fix it, now, because chances are, it'll let you down in the long run.

In response to dahoyle's quote; AMEN!
 

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I just get tired of seeing young guys that don't have enough money already thinking they need things they don't. This is a fun hobby. We need all types here.
I see that you posted again while I was typing the last post. Let me add this concerning the quote above.

That quote is 100% truth in all aspects, and I am right there with you in trying to find a cheaper or more innovative or different way to accomplish something. However, innovation in your solutions must include safety and longevity, otherwise it simply becomes jury-rigging.
 

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Now I know that you did not ask, but I am going to offer you an educated guess as to what is going on inside your torque converter and transmission right now, and what I am speculating the resultant damage to be. If I understand your description correctly, the only mechanical connection between your engine and your torque converter is three bolts fastening the 'wave ring' to the lugs on the converter, and the snout of the converter is not coupled to, inserted in, or otherwise properly lined up with the back of the crankshaft. If this really is the case, (and right here is where I gotta say HOLY SHIT!! :eek: ) then it is it is my speculation that you are destroying the converter clutch and front pump bushings, and are probably going to crack the snout of the converter where it is welded on. You will probably also ruin the front pump, partially from the converter snout wallowing around (will wear/break the drive tangs on the pump gear) and/or partially from all the fine pieces of metal that will get pumped through it from the bushings and the converter clutch.
This is not what happens, the converter snout, pilot, whatever it's called sits in where the Th400's was and is the same diameter. This is how mine is, i'm at 2k+ with the adapter ring and no problems so far, well with the ring at least. It cost me about 45 dollars including shipping to get a ring made and get the right bolts for it. Balancing still won't be perfect even with the right ring, if you ask me, but it has worked so far.

My approach is also not an end all sollution, the right way if you ask me would be to get a converter with the right lug pattern on it. I wasn't sure if i wanted to keep the 700r4, so my 45 dollar experiment was much cheaper than dropping 300+ on a custom converter.

The 700r4 in updated stock form is not a terrible transmission (not saying it's good either ;) ), but mine has its issues. The governor in mine sticks, sometimes it won't shift until really high in the rpms, I'm guessing around 2700 (no tach) because acceleration levels off a lot and i have to have it WOT for it to eventually shift. If i keep it WOT at this point, it will smoke the clutches when it completes the up shift. Mine at least, can't take ALL the power the 4bt can put out at the RPMS it puts it out at.
 

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This is not what happens, the converter snout, pilot, whatever it's called sits in where the Th400's was and is the same diameter.
However I was a bit concerned about vibration(bolts and slots not balanced) and the possiblity of the TC not being centered properly as the tC doesn't engage the snout in the center of the crank.
Now if I have misunderstood what he is saying, I am sorry. However, it says right there in his own words that the converter snout does not engage the rear of the crankshaft. And I cannot believe that taking out his 1/4" worth of spacers would be enough to fully engage the snout if it wasn't touching to start with.
 

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However, innovation in your solutions must include safety and longevity, otherwise it simply becomes jury-rigging.
Well said. With all the time one will put into a swap like this, saftey and "Doing it Right, the 1st time" should be a priority.
 

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Working on cars is a hobby for me. I'm not rich. I do all my own work. When I can I come up with my own solution before buying someones kit. The original hotrodders did it all themselves. I've seen engines dissassembled and rebuilt on a piece of cardboard in the dirt driveway over a case of beer. There is a time and a place for everything. Too many wealthy car enthusiasts will lead the new guys to think that if you don't have the latest carbon fiber reinforced balanced and blueprinted billet titanium CNC machined in a hermaticly sealed QC inspected work environment that their engine will catostrophicly fail at any moment probably killing everyone within the blast radius. I just get tired of seeing young guys that don't have enough money already thinking they need things they don't. This is a fun hobby. We need all types here.
Amen, Brother!

Beyond the family involvement with wrenching, doing my own work has been a hobby / necessity for many years now. I've had one new car that I financed in my life, and that was enough to make me re-think the whole transportation scenario. Since then, I've always been open-minded as to alternative solutions to making what you want, and working within a budget.

But, that said, the thing that can bite you is the "cheap" solution that costs more money in the long run. I personally avoid making permanent modifications to parts that are unique or otherwise hard to replace. That wavy ring counts as one of those type parts.
 

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Now if I have misunderstood what he is saying, I am sorry. However, it says right there in his own words that the converter snout does not engage the rear of the crankshaft. And I cannot believe that taking out his 1/4" worth of spacers would be enough to fully engage the snout if it wasn't touching to start with.
sorry, i didn't read his post fully, just yours. Maybe my setup is different, but mine sits where it is supposed to in the end of the crank. I wouldn't have done it any other way.

I want to say that it the snout is tapered and only the end of it acctually touches the end of the crank, this would mean that full engagement would be relative and 1/4" of engagement should be enough.

if this works: http://picasaweb.google.com/phillyzj/Durango/photo?authkey=O7vI5qU3XbQ#5117192759146522386
 

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But, that said, the thing that can bite you is the "cheap" solution that costs more money in the long run. I personally avoid making permanent modifications to parts that are unique or otherwise hard to replace. That wavy ring counts as one of those type parts.
absolutely. If i can't find a replacement easily, i do my best to not modify it or, do as much research as i can before i do.
 

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Discussion Starter #15
snout

When I started this post I should have written it more just to say what I had done and what was happeneing and that I would continue to report on it. Anyway. The "nose" in the center of My TC is inside the "snout" on the 4bt crank. It is not however pressed firmly against it. If I rotate the it so the pads are not lined up with the holes on the ribbon it will go forward about another 3/16" or so before the snout bottoms. Originally when I heard about a "pilot adapter "which is actually the "snout" I thought maybe there was another loose peice that inserted into the snout to take up the gap. (something I didn't have). Evidently this is not the case..............Well If my TC is off center it is not by much. If it's going to Self destruct, I hope it takes awhile. Today I drove home in 3rd gear with the TC locked. Vibes at 60mph are very low. This leads me to beleive the vibes in OD are mostly just the engine lugging as I go up slight grades at 50-60mph................
I'm not going to grapple any more with the tranny for now. I got a 5M target coming up in the form of reworking my vacuum pump bracket. After that I'm trying SVO.. If the tranny breaks I'll tell everyone about it. Consider it a daily driven test.
 

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Question - how did you connect the TV cable?
 

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http://picasaweb.google.com/phillyzj/Durango/photo?authkey=O7vI5qU3XbQ#5117491598676011010

if you were asking me.

mileage is alright, my 700r4 doesn't like 1st gear, the governor sticks and most of the time i am driving it starts out in 2nd, yay. anyways, it has been getting like 20-24 depending on driving style and if i'm towing, i've towed up to about 3k so far. I am hoping to get some good loaded figures this weekend, unless my 700r4 gives up the ghost. this is all with 3.55's and 31's.
 

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http://picasaweb.google.com/phillyzj/Durango/photo?authkey=O7vI5qU3XbQ#5117491598676011010

if you were asking me.

mileage is alright, my 700r4 doesn't like 1st gear, the governor sticks and most of the time i am driving it starts out in 2nd, yay. anyways, it has been getting like 20-24 depending on driving style and if i'm towing, i've towed up to about 3k so far. I am hoping to get some good loaded figures this weekend, unless my 700r4 gives up the ghost. this is all with 3.55's and 31's.
I was asking anyone that would answer! Is that arm on the throttle lever part of the stock pump, or did you add that also? I need to get some time to do a search here and find out more about mating the 4bt to the 700R4.

Question about your fuel tank - is that pickup part of a kit from Holley?
 

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I was asking anyone that would answer! Is that arm on the throttle lever part of the stock pump, or did you add that also? I need to get some time to do a search here and find out more about mating the 4bt to the 700R4.

Question about your fuel tank - is that pickup part of a kit from Holley?
arm is part of the TC cable kit from bowtie overdrives

fuel pickup is a walbro part, the rest is custom.
 

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i modified the holes on my wavy ring about 9000miles ago.
1st the converter bolts backed out. 1500m ( i replaced with studs and nylocks nuts)
2nd wavy ring cracked in 4 places. 9000miles (welded)
3rd wavy ring cracked again. 9300miles
Thats with no towing and extreme off roading.

In search of wavy ring...
But 700r4 works great...
 
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