My Camaro had a 377 in it when I got it in 2010. Ran it hard for 2 years and loved it. But it was not very well suited for autoX and more at home on a road course. It still really lacked the low and mid range torque. Once it woke up around 4500-5000 (mine had a pretty darn big cam) it was a fun thing. I had the rev limiter set at 7400 most of the time.
For an all around motor for both venues I would build something with more cubes and a little more stroke. If I was building something from scratch I might do what the 410 cube sprint cars run...... 3.80 stroke or right around there.
As you probably know those stock 400 blocks aren't very well thought of.