Re: Breather Tubes
DO NOT DISABLE THE PCV SYSTEM! It will not gain you any power, all it will do, like mentioned, is jeporadize the longevity of your motor.
Do some research on the PCV system, at least half the articles you find on it will offer the opinion; "Even if the manufacturers weren't forced to add PCV in the 60's by emmissions regulations, they would have added it on thier own by the 70's, since the system is so effective at protecting the motor oil and interior of the engine."
The PCV valve is a flow control valve, that only lets the motor suck just enough air, and only in one direction, to keep fresh air moving thru the crankcase. It won't suck enough to effect the engine power or performance in any way, but enough to clear out all the fumes, moisture and corrosive effects that would otherwise linger in the crankcase. Moisture mixing with motor oil is the #1 cause of Sludge, which gunks up the motor and can ruin an otherwise perfectly good motor.
The PCV Valve costs about $3, so if you do anything, you should be replacing it every or every other tune up, since they can go bad. When they go bad, they either don't ventalate the crankcase well enough, let oil get sucked past it, or let enough air flow that it does effect engine performance. So keep the motor running a long time, by keeping the PCV working well.
The Tube in front that runs to the air filter. Like mentioned, you can replace that with the little air filter if you like. Jeep/Chrysler is just trying to save a little money by sharing the breather port with the existing air filter, instead of adding a 2nd air filter. Thats the port that fresh is sucked into the crankcase, whether the fresh air comes from the air filter box, or from a filter right on the valve cover, I doubt would make much of a difference. The air filter box might be a little cooler, I doubt that would have any effect on anything though. Just as long as the air is filtered, you don't want to suck dust straight into the crankcase to mix with the oil.