Welcome to the magnifiscent world of hondas. And welcome to our forum.. Always great to see another crx'r. Nope, the cold air and cat back shouldn't mess anything up. To lighten your car up... hmmm... alot of people are going to say rip all the interior out... but I don't think your in for the my car is ugly as sh!t on the inside look. Theres always a carbon fiber hood. Also I think your year CRX came with the seat belts mounted into the doors. You could get the doors from the 88 crx that doesnt have the seatbelt assembly in the door, but then you'd have no belts.. could always get racing seats and harnesses.... If you have a sunroof, you could replace it with a fiberglass panel. Removing all the A/C components will take quite a bit off and give you some more notisable power, did on my car . Thats all I can think of for now.. Hope that helps a little... Welcome again.