I have a 1990 Integra GS that I know doesn't have the stock engine in it (we bought it with a salvage title from theft), what is the easiest way to find out what engine is in it? I can't manage to find the title (stuff happens when you have a car for 14 years).

Also, under braking it will pull fairly hard to the left. The person who we loaned it to for a while seemed to think it was the master cylinder for some reason, does this make sense and how difficult would it be to replace or rebuild it?