Torque converter questions

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mtnmankev

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How can one ID a torque converter as to application, etc when there are no decals or numbers stamped on it?
With all the different torque converters floating around, how does a person know what transmission it's supposed to be used with, how do you know the stall rate, etc ...

I have a couple of them here that I might want to use as cores (we all know how funny parts stores are wanting cores back) and I hope to get as close as possible to my application when I hand them a core, I don't want them to tell me the one I hand them is wrong and they nail me for more money.

Also, a rebuilding question - when one buys a rebuilt/remanufactured torque converter, does that mean they actually cut it open, do work on the innards, then reweld it together and balance it again, or do they simply flush it "clean" and call it good and resell it?
 

Turbo4whl

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Should be cut open, new clutches, piston seal and new sprag. In some cases fins are rewelded, depending on the model.

Hi stall convertors are smaller in diameter than the factory convertor. Transmission engagement tangs are different between different models and locking convertors, (with clutches) have 3 sets of engagement tangs.
 

78C10BigTen

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Should be cut open, new clutches, piston seal and new sprag. In some cases fins are rewelded, depending on the model.

Hi stall convertors are smaller in diameter than the factory convertor. Transmission engagement tangs are different between different models and locking convertors, (with clutches) have 3 sets of engagement tangs.
Youre a very knowledgable guy Wayne!
 

Matt69olds

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There is a ton of knowledge and fabrication in custom converters.

As for a stock remanufactured converter, any reputable rebuilder cuts open the converter on a lathe. You have to cut just the weld, not the converter itself. The internal parts are then cleaned, worn/damaged parts replaced, then the internal clearances are set up, followed by welding on a machine. They are then leak tested, and balanced. Once the shiny paint goes on it’s ready to be used.

As for custom converters, the overall diameter, pump/stator/turbine fin angle, the size of the windows machined in the stator, the shape of the stator, all relate to stall speed.

Since most performance converters started life in economy cars, needless to say they need a bunch of modifications to handle big power in a heavy car/truck. One of the more common modifications is called furnace brazing. The fins in a low performance converter fit into slots, or have tabs That are folded over into grooves. Needless to say, work them hard, the find loosen up. Furnace brazing bonds the find solid, they won’t move.

The angle of the fins can sometimes be bent, or a pump/turbine from a different converter can be used to get the desired stall speed. Same thing with the stator, sometimes a different part is used, or if it’s aluminum it can be machined. If nothing is available, custom stators can be made from steel.

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There are at least 5 videos about converters (told you it was pretty extensive!) but watching just the first one will give you a little insight
 
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