The B18C5 is rated at 195 hp at the crank.

The K20a is rated at 220 hp at the crank.

Expect at least 15% drivetrain loss and you have the wheel hp numbers. Also, expect to pay around $8k+ for a full K20 swap. For that, you could rebuilt your current motor, turbo it, and run circles around a K20 swapped Integra any day.