This page is under construction... apologies in
advance for incomplete info.
Note! you can get a larger size view by
clicking on many of these images. Beware that the larger images are REALLY big
Shown here is a picture identifying the changes that are
implemented during the installation of the ESS Supercharger system for the
BMW 330i/ci/cic motor. These modifications are as follows:
The OEM airbox and intake ductwork is removed, and not
reused as part of the kit installation. The Mass AirFlow (MAF) sensor is
reused (this is an expensive part!), but is recalibrated by a resistor in
the extension cable shipped with the kit.
WHY: The stock airbox is no longer needed, as Supercharger replaces
the air intake portion of the engine, including the filter. The MAF needs to
be recalibrated to account for the temperature difference between the
incoming cold air, and the warmer intake air after it has been compressed by
The oil dipstick tube is replaced with a new, modified OEM
tube supplied in the kit. The modification is to add a fitting for the oil
return hose from the Vortec unit. ESS does this by drilling out a hole in
the tube, then welding on a small bent tube with a flange stop for the hose
that is pushed on this new port on the tube. The kit comes with this hose
already attached to the replacement tube. The mounting bolt for the dipstick
tube also serves as a mount point for a support bracket for the Vortec unit.
WHY: The Vortec supercharger is oil lubricated, so there must
be a drain path for the oil leaving the blower. ESS chose to provide a drain
path through the bottom of the dipstick tube, which is a clever solution,
given the tube's convenient proximity to the blower, and the use of this
method already by BMW for a stock drain from another part of the engine. The
modified tube places the new drain right next to the existing one.
One of the power steering fluid hoses going to the reservoir
canister is rerouted with a supplied extension.
WHY: Needed to clear the bottom of the Vortec unit.
The power steering ATF servo fluid reservoir bracket is
replaced with a modified OEM bracket that can clear the main supercharger
WHY: One of the two mounting points on the bracket interferes with
the large plate/bracket for mounting the V2SQ (location #2 in the picture). It appears that ESS uses an
OEM part here that they have simply drilled out the two spot welds holding
on one of the two sub-assemblies on the complete bracket, and removed it. In
the modified configuration, the ATF reservoir is only secured by one bolt to
the engine, however this looks to be more than mechanically sufficient.
Pressurize oil to lubricate the Vortec unit is supplied by
making use of the oil pressure sensor port on the engine. The stock oil
pressure sensor is removed, screwed in to a supplied divider (1) that has a hose
(2&3) coming from its other port to feed the blower, then the divider is bolted in
to the original oil pressure sensor port on the engine.
WHY: The blower needs lubrication, and this is a convenient location
to tap into pressurized oil from the engine.
The oil breather hose is rerouted to the intake port of the
Vortec unit, from its original path into the intake manifold. The
replacement oil breather assembly shipped with the kit turns this part of
the motor into a vacuum actuator for the supercharger assembly bypass valve
(see below for an explanation of the bypass
WHY: This modification closes off the intake manifold to essentially
a sealed space with only the throttle and intake valves as openings.
Therefore, when the throttle butterfly is closed, the engine cylinders are
able to create a substantial vacuum in the intake manifold, that is then
used to operate the bypass valve for the supercharger. My speculation (ESS
doesn't explain the rerouting of the oil breather) is that with a connection
to the crankcase through the oil breather assembly still intact, there isn't
sufficient vacuum generated to correctly operate the bypass valve. The
crankcase oil breather is alternately routed to the intake of the blower,
serving the same purpose as when it was feeding the intake manifold,
recirculating piston blow-by (oil and fuel vapors) to the intake path where
The OEM fuel injectors are replaced with larger, higher flow
injectors. The fuel rail mounting bolts are replaced, and the rail is
elevated by supplied spacers to accommodate the larger injectors. A bit of one
of the injectors can be seen in the inset photo outlined in red, the wiring
harness is outlined in blue, and the spacer for the fuel rail to accommodate
the taller new injectors is circled in green.
WHY: The blower increases the mass of air entering the cylinders by
about 50%. This requires approximately 50% more fuel to achieve the right (stochiometric)
fuel/air ratio, and get efficient, complete combustion without the creation
of nasty polluting combustion products (NOx). The Engine Control Unit (ECU)
varies fuel delivery by controlling the activation interval for the injectors
when delivering fuel – the fuel system operates under a regulated, constant
pressure, so the fuel quantity is proportional to the "open" interval for the
injector. This presents a fundamental problem however: As more power demand
the engine and RPM increases, the injectors must stay open
longer to deliver the correct amount of fuel – yet, the increasing RPM
allows less and less time for the injectors to squirt gas and make it within
the available timing window as the cylinder cycles. With the greater fuel
requirement imposed by the boosted air, the stock injectors can no longer
meet the demand within the engine timing window -- so larger injectors, able
to deliver more fuel than the stock injectors for the same given activation
pulse, solves the problem.
Intake air temperature sensor (IAT) is relocated from the intake
manifold to the interior air inflow box (where the replaceable air filter is
WHY: ECU calculations and programming depend on an accurate measure
of the intake air temperature. The blower heats the air as it is compressed.
The intake manifold, the stock location for the IAT sensor, is downstream
from the blower, so measuring ambient air temperature there is no longer
accurate. Relocating to the interior airbox is a good solution, as there is
always airflow through there.
A smaller support bracket is mounted using an existing bolt
from the oil filter canister.
WHY: Mechanical support for the main Supercharger mounting
The main Vortec support plate is bolted on to the front of
the engine using the two existing alternator mount points. One of the
original bolts is reused, the other is replaced with a longer bolt and
spacer supplied with the kit. There is also a drive belt idler pulley that is
replaced with a new one supplied with the kit. It appears to be the OEM
pulley with the locating tab machined off (when you install the kit, the
reason for this is obvious). The two support brackets mentioned previously
are also bolted to this plate for additional support.
WHY: Provides main structural support for the V2SQ.
The MAF connector is extended with a supplied cable that
includes a resister inside the shrink wrap tubing of the extension.
WHY: Necessary to reach the new location of the MAF. The resistor
provides the recalibration necessary to account for the compression heating
of the air from the blower.
The Vortec V2SQ Supercharger unit is bolted into the support
plate from behind.
A new, longer serpentine drive belt is provided to
accommodate the additional loop to the V2SQ pulley.
Two mandrel bent steel duct tubes are installed. One is
connected from the blower intake to the MAF and from there to the new K&N filter in the left
front bumper via a flex tube, the other connects from the discharge to the
throttle body on the motor. Connected between the two metal tubes is a
bypass connection consisting of a rubber hose and a bypass valve operated
via a vacuum line from the intake manifold, derived from the replacement of
the oil breather assembly.
The top radiator hose is replaced with a new one supplied in
WHY: The shape of the original hose interferes with a new, additional
idler pully on the main supercharger bracket necessary to route the drive
belt over the SC pulley. The new hose is formed with a different routing
path as seen in the picture to the right.
This is a picture of the Vortec Supercharger unit before it was installed. I
took this actually to document some damage to the drive pulley that the unit
arrived with, so that I could email ESS the image and get a replacement pulley.
Here's a shot of the engine and Supercharger. Supercharger is on the right, where
the factory airbox (containing the air filter) used to be.
Here's a shot of the
nearly finished install, before the
replacement drive pulley and reprogrammed ECU arrive from Norway. The radiator hose (shop rag stuffed in engine port where this hose
attaches), main cooling fan, and radiator trim cover can't be reinstalled until the
new pulley is installed -- gotta take the main drive belt off to do that.
A side shot of the system with a better view of the tubing.
These are steel tubes bent on a mandrel. The lower tube in the photo is the
intake, and is attached on the left to the Mass Airflow Sensor and then a flex
tube that goes down into the front left bumper where the K&N cone filter is
located to inhale the coolest air possible. The other end fits into a 90° rubber elbow (that
bends to the left in the picture) feeding the intake to the blower. The upper
tube that comes off the blower is the pressurized discharge that feeds into the
throttle body of the motor. Connected between them is a smaller diameter bypass
connection, made up of a short rubber hose and a bypass valve, with an even
smaller rubber hose plugged into the top that provides vacuum to operate the
It works like this: When you place demand on the engine by
stepping on the accelerator, the throttle butterfly opens and passes intake air
to the intake manifold. As such, the vacuum in the intake manifold decreases
because of the open throttle, and in the case of the supercharger, it is
actually at pressure higher than atmospheric (with a 7psi boost, 22 psi vs. ~15 psi). The control
hose on the bypass valve is connected to the intake manifold. Because there is
no vacuum in the control line relative to the ambient pressure around the valve,
it closes, cutting off the bypass path. This ensures full, boosted air to the
When you take your foot off the gas, the throttle closes,
cutting off the intake manifold from the intake feed from the Supercharger.
However, the supercharger is still spinning at whatever speed the engine is
going, despite the fact that the engine isn't producing power. This creates a
significant overpressure situation in the tubing between the blower and the
throttle body, and the air has to go somewhere. So, absent a bypass, all sorts
of nasty hissing takes place and other ugly noises as the pressure backs up in
bypass valve. When the throttle butterfly closes, the
intake manifold becomes (for all intents and purposes) a closed space. The
action of the valves and pistons produces some serious vacuum in the intake
manifold, as the engine under these conditions is essentially an expensive air
pump (the ECU cuts off fuel under such circumstances). This vacuum is use to
open the bypass valve on the Supercharger ductwork which connects the intake and
discharge tubes together, allowing the pressure from the discharge to simply
route around back to the intake. Voila! No hissing or other scary noises coming
from the supercharger.
Here's a shot of the Intake flex tubing going into the front
left bumper where the new air filter is. The front of the car (and left
headlight assembly) is at the upper left; you can see a little bit of the
Supercharger mounting bracket in the lower right.