Can anyone let me know if there is a good header and cold air intake designed for this model (e46) yet?

Why would you want headers for the E46M3... they are already equal length headers that are race inspired. The only thing I could think of would be to eliminate the cats (as they are built onto the factory headers). But if you eliminate the cats you are going to get a cE light.

I had a 98' M3 that I put the works on. i.e. Dinan S3 (#016) package, RMS intercooler (the second one Osh made) larger/smaller pulleys for a total of 10.5 psi boost, high flow cats., header and modified intake plen. This made 318 RWHP as per the chassis dyno... very nice. Just sold it six months ago to a guy in CO.

With the problems that BMW has had with head gaskets... I don't think I'll be going forced induction with this car... so I need to make more power with the cubes I have. There are a few good cat backs, but there isn't much real power in them for the money... 4-8 hp depending on who you believe. I have been told that other than the cats. the real restriction on the 54 is the header. I would go for high flow cats as well if there are any. The cold air intake has been a problem as well because the mass air flow is integral with the air box... so I'm just asking if anyone knows how we can make these go... thanks!

The stock intake is already a cold-air intake, but GruppeM has brought out a new CAI assembly which replaces the stock assembly for better airflow. I haven't seen any tests yet to prove this, but that is what I hear. Actually the MAF sensor is removable by two screws from the factory airbox.

I haven't heard that the headers on the S54 engine are a bottleneck other than the fact that the cats are built directly onto the headers. If you replace the headers, you are going to have to do some major surgery to install cats (if you want to) to the exhaust piping. Maybe Supersprint makes some headers...

SuperSprint does make headers for the car. You have to add a boss for the O2 sensors and they will work without a CEL.

The do apparently make more noise.

There has been a lot said about CAIs. Jim C. says tests he has done show only a max of 3 hp from air filters/CAIs.

Originally posted by Kevlar
The stock intake is already a cold-air intake, but GruppeM has brought out a new CAI assembly which replaces the stock assembly for better airflow. I haven't seen any tests yet to prove this, but that is what I hear. Actually the MAF sensor is removable by two screws from the factory airbox.

I haven't heard that the headers on the S54 engine are a bottleneck other than the fact that the cats are built directly onto the headers. If you replace the headers, you are going to have to do some major surgery to install cats (if you want to) to the exhaust piping. Maybe Supersprint makes some headers...

The headers are the bottle neck on the s54. I am hearing 10+ hp gains by changing the headers. There are always ways around the CE light.

Is anyone using the SS header on your own cars? It sounds like I'm hearing that I could get 20 HP for 4k of parts (SS header, Eism. EX, GruppeM CAI). This is not an e36 for sure! Has anyone done this? How difficult is the OBDII in all of this? Thanks again!