Rear Brakes:
what year and model crx do you have? 90-91 crx si came with rear disc brakes...if you have rear drums you can also get the who rear lower control arm assembly from a crx si (90-91) civic ex sedan (88-91) or a 2g teg (90-93...much more common)...these are also 9.5" but significantly reduce brake dive b/c they brake better

Front Brakes:
2 avenues you can take...ugrade your current 9.5" brakes for more powerful calipers such as 4 piston kits available for the 9.5" system

get a larger brakes such as 11" integra front brakes and even get 4 piston calipers for maximum effectiveness (www.fastbrakes.com)

All 4 Corners:
get stainless steel brake lines all around for better performance when it gets hot out (rubber is known to cause bulging reducing braking effectiveness)