727 rebuild and 9 1/2" converter swap

[msbaugh]

You Might have seen a couple of my older posts. I've got a 440 and i'm rebuilding a 727 to put back in which was running fine before it broke. Crank isn't drilled deep enough for a 4 speed so I'm going to stick with what I've got.

I'm almost positive it's a forged crank. It has a 1" thick dampener up front with no weights or holes drilled into it. After removing the transmission I realized I should've indexed the torque converter because it Has one 2" x 3/4" weight tack welded onto the outside. The flex plate also has a small hole drilled into it.

I want to switch the pos tci converter I have now to a 9 1/2" converter when I rebuild the 727. How can I match the converter weight when I switch and how would I index it to make sure this 440 stays balanced?

Sorry for the stupid questions

[msbaugh]

Just kidding... The dampener does have a hole in it, it was just covered by timing tape so I couldn't see it!

[msbaugh]

Here ya go

[1 Wild R/T]

You do have a steel crank... And you weight on the convertor is probably just balancing the convertor itself to zero... The flex plate only bolts to the crank one way do to a bolt staggered slightly.. And the flex plate only bolts to the convertor one was again due to a slightly staggered bolt... ///typically the convertor drain winds up 180 degrees from the small hole in the flex plate....

[mopar jack]

The hole in the flex plate will line up with a notch on the crankshaft flange.

[msbaugh]

gotcha! So.... How do I get the weight on the new converter right since I'm going to a 9 1/2 from the 10" tci I have that needs to be replaced

[1 Wild R/T]

The new convertor should already be neutral balanced.. Just bolt it in...

[msbaugh]

Understood I just have my doubts with that hole drilled in the harmonic balancer that that weight on the converter was used to neutral balance it. Seems like a lot just to neutral balance the thing.  And tci street fighters don't all have those weights from what I've seen. I can't find a shop that can spin it and check its balance

[1 Wild R/T]

Convertors take special equipment to balance because you need to balance the stator, turbine & impeller then weld it together & support the stator & turbine while you spin the impeller & cover....   Then if it's intended to be used for a externally balanced combo weight is added based on a template....   A weight the size you show likely is just balancing the convertor..... It's pretty thin, Externally balanced 440's have small weights but probably twice as thick as what you show plus twice as wide and there are two of them....   I've seen holes that size in plenty on balancers...

[msbaugh]

Convertors take special equipment to balance because you need to balance the stator, turbine & impeller then weld it together & support the stator & turbine while you spin the impeller & cover....   Then if it's intended to be used for a externally balanced combo weight is added based on a template....   A weight the size you show likely is just balancing the convertor..... It's pretty thin, Externally balanced 440's have small weights but probably twice as thick as what you show plus twice as wide and there are two of them....   I've seen holes that size in plenty on balancers...

Thank you for the explanation! I'll give a zero balance converter a try! No one locally could give me an answer so I resorted to this website again. thank you for responding! I'm a noob to these old things and have been learning as I go, my car is almost 20 years older than I am! The last trans shop I talked too hadn't externally balanced anything for over 10 years... Lol... So they didn't know what to tell me

[msbaugh]

And the weight on the converter is 1.5 oz if that helps