Please me some torque on converters

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Valkman

Valkman

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I'm the process of swapping out externally balanced 340 for a internally balanced for 408. I have 3 converters the one used on tge 340 seems to have a high stall, and the other two are supposedly stock 318 converters. I know very little about tq's, and there are no significant markings to tell these apart. The cam I'm going to run is a fairly mild Street cam rated at 1800 stall.
The converter used in the 340 seems to have extra weights
20170303_150508_HDR_resized.jpg

versus the other two
20170303_151315_resized.jpg

They all measure about 11 inches across
20170303_145944_resized.jpg

is there a way to determine what the stall is I need to use converters?
 
Those are manufacturing balance weights from when the converter was built and balanced.
Motor balance weights are usually on the engine side of the converter and a lot thicker.
A 318 converter is going to stall higher in your 408 than it did behind a 318, so keep that in mind.

Which one is which?

No idea.
 
I should have also pointedout that it's a 904 trans:D
 
Correct as said above..those weights are to balance the converter...nothing to do with externally balanced engine...those are on the face of the converter.
 
There are other extra weights that I can see on it?
 
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1968 and up 904's behind either the leaning tower of power or the 318 used two converters, one classed as a high stall and the other a low stall. The factory placed decals on the side of the converter, the low stall had a triangular decal that said "lo stall", and the high stall had a round decal that said "high stall". There are various opinions as to what stall these things are: the low stall around 2000 rpm and the high stall around 2300 rpm. Depending on who you talk to these stall speeds can/will vary. There are NO weights added to these converters as TrailBeast explained, and if there are any weights welded to the front(engine side) of the converter, somebody has added these weights for whatever reason.
There is a way to tell if the converter is a low or high stall even if the decal is missing. Chrysler in their wisdom stamped a code on the hub side of the converter. It is a 3 number code. Not at times easy to see, but worth while looking for. If you find this number, I might be able to help you further. Also, the converters from the photos look like they have been rebuilt in the past at some time, so there might be either a painted or stenciled part number on it. Most if not all converter rebuilders will put their own part number on it. The shop I worked for in the past would have stenciled part number 762 on it before putting the converter in stock.
Make sure before you chuck one of these in (they look used to me), that any oil inside is pink, with no debris in the oil, and that the hub that goes into the pump is as smooth as a babys bottom. If the hub shows any sign of wear (run a finger nail down it) it'll leak and could cause the pump bushing and front seal to fail. Also, look very closely for any sign of cracks in the hub were the pump lugs fit into. Most converter rebuilders will automatically replace the hubs on Chrysler converters for this problem.
Used converters IMHO make great door stops.
 
wow - be careful!! after putting up what had to be some good coin to do a 408 (stroker 360 right?) you don't want to put a TC behind it that's incorrect and/or not up to the task. May I suggest you read this: Identifying and exchanging TorqueFlite automatic transmissions
~~of particular interest is this paragraph: "For small blocks, 360 engines and some 318 engines of the LA family are externally balanced. They use specific balance weights on the torque converter, and are not the same between the 318 and the 360. The 340 engines in 1972 and 1973 used cast cranks, and thus used their own unique externally-balanced torque converters also."
I know they are somewhat expensive but, put a few bucks into an aftermarket TC. Decide who you want to use and call them - they will have the technical knowledge needed to make an informed choice.
 
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ScampMike said:
360 engines and some 318 engines of the LA family are externally balanced.
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Neither of them have external weights other than the thin strips in the photos. The high stall that was with the 340 (73 externally balanced) go figure. One of them I have no knowledge of. The gray one came out of the an old drivetrain I had in the car that drove fine, but I didn't drive it much because the car didn't have a windshield at the time, so I don't remember much about the stall.

Transman l take closer look for those numbers.
 
Valkman said:
Neither of them have external weights other than the thin strips in the photos. The high stall that was with the 340 (73 externally balanced) go figure. One of them I have no knowledge of. The gray one came out of the an old drivetrain I had in the car that drove fine, but I didn't drive it much because the car didn't have a windshield at the time, so I don't remember much about the stall.

Transman l take closer look for those numbers.
Click to expand...
To the best of my knowledge the 340 never came with a 904. I know that the 71 Duster 340 I bought brand new had 727 in it and so has every other 340 I've ever looked at. Send us a photo of the engine side of the 340 converter and also give me the diameter of the converter hub.
 
ScampMike said:
wow - be careful!! after putting up what had to be some good coin to do a 408 (stroker 360 right?) you don't want to put a TC behind it that's incorrect and/or not up to the task....
I know they are somewhat expensive but, put a few bucks into an aftermarket TC. Decide who you want to use and call them - they will have the technical knowledge needed to make an informed choice.
Click to expand...

This is exactly what I was thinking. Don't cheap out now. I had a custom converter built for my 408 for $350 at Continental Converters. Lots of factors go into building a custom converter. They wanted to know everything about my car except the previous owner's middle name.

I wouldn't use an off the shelf aftermarket converter either let alone a stock 318. Just my two cents. Good luck!
 
transman said:
To the best of my knowledge the 340 never came with a 904. I know that the 71 Duster 340 I bought brand new had 727 in it and so has every other 340 I've ever looked at. Send us a photo of the engine side of the 340 converter and also give me the diameter of the converter hub.
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This is in a an early A, the 727 doesn't fit without modification so I'm using a 904. And guys this is not a race car and I'm thinking a stock converter will suit my needs just fine, I'm just wanted to find a way to determine the stall.
 
Valkman said:
This is in a an early A, the 727 doesn't fit without modification so I'm using a 904. And guys this is not a race car and I'm thinking a stock converter will suit my needs just fine, I'm just wanted to find a way to determine the stall.
Click to expand...
maybe we just don't have enough info here - but at this point, I don't think any of the three you have will work.. The 904 uses a 10.75" converter and the 727 uses either a 10.75 or a 11.75.. there is also the spline count issue as well as the balance type. Did you read the allpar article I posted a link to?
 
It's a 904 transmission, and all these came out a 904. As far as the spines the transmission is out of later model 73 Duster so I think they'll fit.
 
I could only find a number on one of them 762E
 
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