340 mild build 727 stall converter question?

I'm just trying to make some sense of normal operation. It doesn't slip when it shifts or anything. It just feels lazy idling from the stoplight unless I'm into it. At that point it comes alive which is not a bad thing. I'm just not used to a small block and a stall converter. Plus it seems to be a little temperamental since it's gotten cold or outside and the tranny acts way better after it gets warm