legacycentral bbs

I was wondering if anyone could give me advice on building a "new" exhaust system for my 91 Legacy Wagon.

Can anything be done to increase horsepower by using newer Legacy/WRX parts? I have a non-turbo system.

I guess not.

N/A system? Might want to try getting an open exhaust system. Other then that, you're pretty much stuck where you are in terms of HP. However, you'll be riding on better mpg then a turbo person.