on a 91 5.0 is there much difference between just putting a k & n filter in the air box (and removing the silencer) and getting the k & n exposed cone filter? it seems the cone might get more air but the regular filter in the air box gets colder air. anyhow is there much difference and is the cone worth the extra money.

OK this is something that I just learned on my 1992 GT. If you run an air filter system with the filter just under the hood then the fan wash will send the mass air meter mixed signals and confuse the computer. If you do plan on upgrading your air filter system the I would go with a cold air system. This puts the filter assembly in the fenderwell and you will not have to worry about air disturbances. One problem I also experienced was this. When the motor was stock I added BBKs cold air induction system. Well once I added the 70mm throttle body the tubing was too small. It basically went inside the throttle body. So I bought the C&L 76mm system. Unfortunately it is not a cold air system so what I did was kept the section from the BBK (from the fender to the mass air as it is 76mm) and made an adapter from that blue material to make the two join. Hope this helps.

Ken