Automatic Transmission - Help me choose a converter

I talked to yank and talked to circle d im getting a good price from both just wondering whats better circle d 4c or yank ss3600?

They are both very good converters. The 4C in the Circle D refers to the STR which should be about the same as the Yank SS series converters. It has nothing to do with the stall speed. For reference I have a Circle D 3C in a TBSS and it is 3600. The STR is a little lower I think around 2.4 -2.5 versus around 2.6 -2.7 for the 4C and the Yank SS series. I think I have it right , but, I am sure Chris from Circle D will chime in.

You can not beat the customer service or their converters from Circle D.