Having both my engine and tranny done currently and the tranny is already finished minus the torque converter. Engine is stripped and they called and reported to me that the crank was a forged internally balanced crank, which I then reported back to my tranny guy so he could order the correct torque converter. He struggled to find a torque converter for a 1973 440 with an internally balanced crank and stated that the cast number on the 727 tranny I had goes to a 400 (the number stamped was 3732564 4290 9809) which then made me doubt I had a 440. Today I called the engine shop and they reported the casting number on my block (36988304405) confirming it was a 440... guess I am looking for some peace of mind if anyone has any!

The tranny was likely switched out at some point, or the engine, or who knows. You're talking about a 41 year old engine and transmission here! What is it out of? Are you trying to make good power out of it? Ask the tranny guy what it has for planetaries and drums.

Forged crank torque converters shouldn't be too hard find, just look for an earlier application, like 1969.

I was told the tranny was mix and matched parts on the inside, 4 clutches. The guy I bought the tranny/engine off of said it came out of a 1973 C body of some sort. I want to definitely do some improvements on the engine and the tranny got completely rebuilt + a shift kit. I guess the tranny guy just wants to be sure that he has the right torque converter on it so it doesnt burn up.

In short a big block trans is a big block trans.

Select your converter for your big block "internally balanced" since your motor is.

If your trans guy can not figure out what converter to select......... well

I see where your coming from - I think he is trying to be 'year' accurate where as I am a more 'run' accurate type of guy

'73 was the first year for the cast 440 crank and not all got the cast crank...have your guy order for a '72 or earlier.

Cool - I'll have him check it out