E39 540i exhaust and intake options

["Hemauer" <shemauer@xxxxxxxxxxxx>]

For E39 owners out there I have some ideas as to inexpensive and effective
intake and exhaust options for the car.

After owning an E36 for a number of years I recently bought a '97 540i 6
spd.  As some on the list may have experienced, the aftermarket for the E39
seems a bit more limited and more expensive than the E36 world.

After researching exhaust options (every comapny wanted big $$$ for a simple
short pipe, muffler and two tips) I decided to go about designing one
myself.  I sourced various mufflers and set up a time with a friend at a
local exhaust shop.  We intended to cut off the stock muffler and then test
fit various systems to find one I liked.  We cut off the stock muffler just
behind the rear diff.  Decided to start up the car like this just to see how
it sounded.  Suprisingly, it sounded great just like this.  We simply welded
on a rear pipe section and turndown and that was it!  The car sounds great,
no highway drone at all - and all for less than $50-$75.

I also designed a cold air intake system for the car as well.  I used a K&N
filter with a short section of 3 1/2" pipe and silicone hose to connect to
the airflow sensor housing.  I then built a sheet metal heat shield that
fits beween the K&N and the rest of the engine compartment.  Also installed
two 2 1/2" ducts from the front of the car to under the K&N to help route
cold air.  Also left in place the stock "snorkel" that attached to the stock
airbox. This also would help route outside air to the K&N.  Results were
excellent.  I tested the system using some OBDII datalogging software.  I
monitored the intake air temp sensor and compared this reading to ambient
temperatures.  From 20 mph on up the intake temp readings were only 2 to 4
degrees above ambient.  (Ambient of 62 deg).  Temp readings at rest would
slowly rise to eventually around 110 deg.

Just some suggestions for those looking to give their E39 a bit of a kick!!!
E-mail me privately with any questions.

Scott Hemauer
'97 540i 6 spd
'95 Mitsu Eclipse GSX
'90 Eagle Talon TSI

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