When is it too much power for the street?

Most of the deaths from so called street racing around here are from kids in underpowered Hondas or in parents BMW's playing cat and mouse through traffic on Hwys and city streets. I really don't consider that street racing that's just stupid.

And for the OP, there's a difference between street strip car and a street only car. On a street strip car sky is the limit cause the main purpose for the power is the track but on a street only car I'd say it's some what questionable for a 400 plus hp Abody and really questionable for a 600 plus one. But if you want an whatever hp car and plan on driving it reasonably responsible then go for it.