Performance muffler problem

Ok i just bought a 1993 honda prelude SR and it needed a new muffler so i was looking to put a perfromance muffler on. I talked to a mechanic my family is good friends with and he told me that over time they can damage your engine? Has anyone ever heard of this cause i really want to know if you've heard or have on let me know thanks

Nope, it won't hurt your engine. People have been upgrading mufflers for decades - one of the easiest and cheapest mods you can do to a stock car. Not a problem.

K thanks buddy i just called honda today and they said basicaly the same thing but if anyone has heard of this problem i probably wont be getting it for another 2 3 months so let me know thanks. And does anyone know what is a good kind of exhaust to get that makes some good noise but not an unreasonable price?