Breathers
 

Just a general question.. What do they do?

They breathe.

diaf . lol

Basically they alow more air into other areas that dont normally get air. The valve covers for instance.

ok grant. that is wrong. sorry. theres no reason fresh air needs to get into the valve cover.

breather are used to replace PCV valves or in the LT1's case, the breather tube. IMO replacing the passenger side breather with a filter makes no sense. you still have the PCV on the drivers side.

PCV systems recycle the blow off and all the crankcase vapors back into the engine, into the intake. the point of a breather filter is to release the crankcase vapors into the atmosphere rather than the intake, keeping the intake charge cleaner.

well this is obviously horrible for the emissions and crap, and i dont see any gain nor purpose whatsoever, so might as well save some money.

I see... Howcome I see some of them on valve covers though? Ive seen that quite a bit.

yeah thats cuz most engines have a breather tube that goes from the valve cover to the intake. its recycling the crankcase vapors into the intake.

by putting the breather filter on it "keeps the intake clean". a ricer mod IMO.

i see... thanks

Well nevermind my shot in the dark. :(

or on older style engines like mine it just replaces the breather tube so that you can put an different style filter on it

Probably guys with turbos/SCs. They need to plug their PCV hole so that the preasurized air doesn't preasurize the crank case. Then the valve cover breather takes the place of the pcv. Anyhow, thats how I understand it.

No, Ive seen many that are n/a.

Its 'mostly' a pointless mod.

On a N/A car its mainly for show, but for us F/I guys its a must. Its also a way to vent off crankcase air on an older motor if you are starting to get blow-by on the rings.