I need some guidance. 360/904 Balancing

I put a 360 together and did cam break in with a built 904 (full manual, reverse pattern). Drove it around for a few days and the novelty of driving it on the street wore off real fast. So I got another 904 in a parts swap (pictured). It is a lock up trans. The converter has three weights welded to it. Two small and a larger one. I know this transmission was hooked to a 360 and installed in a first gen Dakota. My questions are do you think this converter is already weighted for a 360? Am I going to use a factory flex plate or the B & M I bought to use with my other transmission? Or do I grind these weights off and use the B & M flex plate?

All the external balanced stock Mopar converters I've seen have bigger weights welded onto the front of the converters, not like yours
I wouldn't experiment with out knowing for sure the converter you choose is compatible with your motor and flex plate first

What Cab said.
On my 406-inch 360 I went with internally balanced but used the stock non-lockup converter & plate.
I dislike external balance for a few reasons, converter hassle being one of them.
The big OEM external-balance weight was easily knocked off, the small left on. Had zero vibrations.
What I don't know is if the external-balance weight was in the same place on all applicable converters.
Seems that way, someone here will know.
I would want to know who did that converter & what's up with it.

Put it in and drive it, report back. It looks like a 360 non magnum to me.

If there's a part number somewhere like on one of those stickers you might want to look it up and see what it's for.
The torque converter that was behind one of my 360s had no big weights but was still balanced right for a 360. Every one I've used since I've had a local transmission shop weld the proper weight on if the converter wasn't balanced for a 360.

This is what I have decided to do. I mean it's definitely not for a 318. So what else could it be? I will run it with the factory flex plate and see how it goes. If no good I will try grinding the weights off and using the B&M flex plate. This engine is going to end up in my Shelby Dakota so I will still need the B&M flex plate when putting to the A500. Thanks for all the input guys.

Every 360 convertor I've ever seen had weights on the front. The weights on the side are to give it a neutral balance. That looks like a neutral balance convertor. If you have the B+M offset weighted flexplate, you can run that convertor. I wouldn't run it with the factory flexplate unless you like pulling the engine back out to put the B+M plate back in. Don't grind the weights of the side. You'll just be creating headaches for yourself and you will end up having to get another convertor. Trust me on this and don't ask me how I know.

[quote=elmor353]Every 360 convertor I've ever seen had weights on the front. The weights on the side are to give it a neutral balance. That looks like a neutral balance convertor. If you have the B+M offset weighted flexplate, you can run that convertor. I wouldn't run it with the factory flexplate unless you like pulling the engine back out to put the B+M plate back in. Don't grind the weights of the side. You'll just be creating headaches for yourself and you will end up having to get another convertor. Trust me on this and don't ask me how I know. [/q

Sounds like the path I should follow. Thank you.

those weights around the circumference are DEFINITELY there to make that converter neutral balanced !
ALL external balanced converters matched to external balanced engines have weights welded to the ENGINE side of the converter.
if those weights [in the front/engine side of the converter] are missing, you need to use a weighted flexplate like the B&M pictured.

Those are neutral balance weights. Mopar external balance weights are always on the front surface next to the pads. If this converter came from a Magnum it would have been externally balanced using the flex plate. I believe the Magnum conveter bolt pattern is symmetrical as well. Magnum and LA use different amounts of imballance.
Dou

X3 the weights on the curve side are to balance the hunk of metal to neutral balance to begin with at the factory when they spin it then weights are added to the flat face if it is externally balanced. the only thing that may or (may not) mess things up is if there is a difference between LA & mag 360's torque converters (in the balanceing) EDIT if no issue there use the 10239 plate & your good if the plate mounting holes are offset (regular 360)

Thanks again all. I am going to drop it in tomorrow with the B&M 10239 flex plate. It is an LA 360, I just have Magnum exhaust manifolds on it.