Could be clutching at straws here, but would I be mad to go up against a new Audi S3 with 265PS in my ST220 which has 248BHP?

The S3 is 30kg lighter, and about 15BHP up yet does 0-60 1.1 seconds quicker than my ST.

Curious to know what the real life difference would be, making full use of the revs; how far behind would it leave me?