I am looking at beefing up my 91 B230F motor without pulling it apart but I,m not quite sure how to go about it. There is lots of sites on doing turbo motors but not non-turbos.

One of the things I've been considering is to use a K&N air filter. I'm not sure if it is best to use one that goes in the standerd air box which gets air from in front of the radiator or a cone one that goes on the end of the air mass metre.

Another thing is what happens if I put in a diferent cam? Do I have to reprogram the computers or does that not matter and are there any good cams avalable?

Someone told me that you can get more power if you disconect the 02 sensor, because then the computer can't restrict the engine's output to keep the emision levels down. Is this true or does the computer need it to run the engine properly?

What other ways are there to improve the engine's performance, extractors, exaust system, spark plugs, coil