New 135i user :D

[Da_Meister_22]

Originally Posted by Stohlen

Oiled filters vs. non-oiled.

guessing the oiled one is better?? lol since is more expensive.

[Stohlen]

yeah its supposed to flow better, but at the same time not catch as much dirt.

[Cozy]

Well it depends on your dealer regarding warranty, some are ok, some are not but bottom line it's an engine mod and an excuse for BMW to try wriggle out of turbo or ignition related claims.

A blow off valve is for noise, the good old turbo motor Tsssshhhh sound however, even though they vent to atmosphere they can still be better at holding shut during high boost experienced during WOT. A diverter valve is essentially the same but it recirculates charge air back into the intake and has no port to vent it externally, it is almost silent unless fitted with a DCI, you can then hear the charge air dump back into the turbo inlet. The OE valves are plastic diverter valves, upgrade to Forge for example for more robust metal ones which will hold your boost for longer in the rev range but that said, the OE ones are ok until age gets 'em.

[Stohlen]

Originally Posted by Da_Meister_22

Last question..promise. What the purpose of this "blow-off valve". Is it just for "noise" or is there a technical purpose for this unit?? lol.

When the engine is in boost (above atmospheric pressure) and the throttle closes, the boost pressure builds up and has nowhere to go. Instead of blowing the intake up, the blow-off-valve vents the excess air pressure to the atmosphere. Most people put on one for the sound, because the stock engine has diverter valves (better known as bypass valves) that vent the air back into the intake.

The engine diverts the air back into the intake system because that air has already been metered and if it is not put back into the intake system, the engine will run slightly rich in the moments following the throttle close. Its not really a big deal but it is slightly less efficient.

There are blow off valve kits offered as well as upgraded diverter valve kits. Both do the same thing, just one is slightly more efficient while the other makes a novel noise.

[Da_Meister_22]

Guys what about these http://www.**********s.com/aFe-Stage...35i-Z4-35i.htm are they efficient, good? I know they were terrible for the E60s...what about the E82?

[Da_Meister_22]

Sorry this http://www.**********s.com/aFe-Stage...35i-Z4-35i.htm

[Da_Meister_22]

IDK why the link is not working, but is the aFe Sealed Air Intake.

[Da_Meister_22]

Guys Im getting the AE from mod bargainss the City Vision Lightning Brand...Are these Good AEs?