A look at some of the claims made by producers of aftermarket electric superchargers/turbochargers.
By Michael Knowling
Click on pics to view larger images
This article was first published in 2004.
Electric forced induction is an area of modification that attracts plenty of
interest. Here at AutoSpeed, we've received countless emails on the subject. It
seems the ability to deliver instant boost pressure - regardless of rpm -
harnesses the interest of every enthusiast. In this story we've put together a
list of aftermarket electric turbo/supercharger companies and presented you with
their claims. This is not a comparison test, but it is certainly a great place
to start looking if you want to take your car to an electric boost stage of bolt-on
The e-RAM electric supercharger has been manufactured by the
US-company eRACING since 1997. There are currently six versions of the e-RAM on
The base level e-RAM 3.0 is suitable for engines up to
5.0-litres and mounts to your existing airbox (ie pre air filter). A 3-inch
rubber adapter is used to attach the eRAM directly to the airbox. The base e-RAM
3.0 retails for US$299. But a variation on this model is the e-RAM 3.0KN, which
comes supplied with a K&N pod filter. In this application, the factory
airbox is removed and the e-RAM is mounted downstream of the K&N pod air
filter (ie the e-RAM draws air through the pod filter). The e-RAM 3.0KN kit
costs US$349 - US$50 more than the version that connects to the airbox.
For even greater installation flexibility, the in-line e-RAM
3.3 comes with adapters on both the intake and outlet ends of the e-RAM. This
enables you to mount the unit anywhere in the intake system - such as between
the airflow meter and throttle, if desired. The in-line e-RAM 3.3 cost US$309.
For maximum performance gain, the Super e-RAM is for you - the
Super e-Ram is essentially a pair of conventional e-RAM units mounted in series.
The Super e-RAM checks in at US$589. Like the e-RAM 3.0, a K&N filter and
in-line mounting versions are also available in the Super e-RAM range - these cost
US$629 and US$596 respectively.
eRACING claims the base e-RAM 3.0 achieves a 4 - 6 percent peak
power increases with strong gains at all engine revs. Up to 15 percent power has
been measured when removing the factory airbox as part of the installation (such
as when fitting the e-RAM K&N pod filter kits).
Note that the Super e-RAM (with two e-RAMs in series) is said
to give a 9 percent gain throughout the rev range and up to 27 percent more
According to the manufacturer, "the eRAM produces less than ½
psi (positive pressure), but also rids the intake system of about ½ psi of
vacuum caused by filter and inlet restriction." These two improvements combine
to give the eRAM its claimed 1 psi supercharging effect. Using the same logic,
the big Super e-RAM puts out up to 1.7 psi.
Compatible with conventional 12-volt electrical systems, the
e-RAM is an axial flow compressor. The e-RAM 3.0 draws up to 50 amps and is
rated at 700 Watts (approximately 1 horsepower). The Super e-RAM places a
100-amp demand on the electrical system.
to eRACING, "there is typically no need to adjust air-fuel mixture - the
computer can handle the e-RAM's small increase in mass airflow." They also state
that power gains depend on existing engine management strategies (ie some cars
will respond better than others).
any case we'd suggest careful before and after analysis of mixtures...
The e-RAM is
triggered by an add-on throttle position switch that 'spools' the compressor to
full output (which is about 22,000 rpm) within one-tenth of a second. The e-RAM
can be triggered at any engine speed, but note that a 100 percent throttle
opening is required - this is because "the choking action of the throttle would
just remove any gains in pressure created by the e-RAM". Engagement of the e-RAM
at only wide-open throttle also minimises the load on your car's electrical
system and maximises the life of the unit. At all other times (when the e-RAM is
not operating) it is said to cause minimal intake airflow restriction. According
to flow bench tests, airflow through the static 3 ½-inch diameter e-RAM 3.0 is
equal to that through an open 3-inch diameter pipe.
eRACING suggests the e-RAM can typically be installed in less
than an hour. It comes supplied with an illustrated instruction manual, wiring,
adapter hose, fan inlet, e-RAM unit, a 50-amp relay and a throttle position
According to eRACING there is no chance of the e-RAM damaging
your engine through component failure. "If anything was to enter the fan and
damage it, any and all parts would be captured by the filter." Note that, in
installations where the e-RAM draws through a cone-type filter, a supplied
safety screen is fitted to the outlet of the e-RAM. The e-RAM electric motor is
rated for over 1000 hours use (which is more than ample considering the
full-throttle only operation) and its composite impeller is apparently very
strong. It is also very heat resistant and features no-maintenance ball
For more information - including warranty and a performance
guarantee - visit eRacing Motorsports
ESC Electric Supercharger
From the BoostHeads.com website; "Thomas Knight is proud to
unleash the revolutionary ESC-400
Electric Supercharger. Our patent-pending
series electric supercharger technology shocks the competition with up to
20 psi of instant boost. Yes, we said 20 psi - in 3/10 of a
Quite unlike anything else on the market, the ESC-400 uses an
Eaton twin-rotor core that's driven by three custom wound electric motors. All
three motors - totalling 18 horsepower - are mounted on a CNC 60-16 T6 aluminium
billet bracket. Interestingly, the ESC-400 has its own independent power source
- four high-capacity 12V batteries, which are designed for very fast
Suitable for use on engines up to 2.5 litres, the ESC-400 is
capable of 20 psi of boost but - on a stock motor - it is recommended that you
don't exceed 5 - 7 psi. Depending on the boost pressure you require, the unit
can produce maximum boost for up to 15 seconds. The Eaton roots-type compressor
comes rated up to 425hp and delivers up to 405 cfm of airflow at 5.5 psi boost.
Note that, like the e-RAM, the ESC-400 supercharger operates only at wide-open
The universal ESC-400 kit - which retails for US$1995 -
includes a boost gauge, solenoids, relays, switches, battery terminals, copper
busbars, ammeter and a 2½-inch check valve. Installation should take a
competent workshop about 12 hours. Note that the ESC-400 draws 600 - 1200 amps
during operation, so specialist electrical system experience is desirable.
And what about the engine management system, you ask? Well, due
to the huge mass of air this unit can supply to the engine, it seems likely you
will need to upgrade the car's standard engine management system. There's no
escaping the fact that huge increases in mass airflow call for management mods -
this is the case when bolting on any supercharger or turbocharger kit.
In its most basic set-up, the ESC-400 battery system can be
trickle charged overnight to give you 15 seconds of boosted performance the
following day. Once spent, full battery charge will then be restored after about
an hour of driving. But, should you decide to fit a 200-amp alternator, you can
restore battery charge in just a few minutes of driving. Note that the car's
alternator is bypassed when the ESC-400 is in operation - this eliminates
The ESC-400 is a great bolt-on for people wanting a big power
hit only on the odd occasion. As claimed, "while you're waiting in the staging
lanes or cruising along the strip, you can relax and hurl insults at the nitrous
guys while your system preps for another 15-second burst of sheer power. That's
more than enough time to run the quarter mile or remind that high school kid
with the neon muffler bearings who his daddy is..."
Interestingly, the ESC-400 is apparently very loud in operation
- it's described "like a low pitched siren, or a vacuum cleaner on steroids."
Durability is a strong point - information on BoostHeads.com suggest the unit
will comfortably outlast your vehicle.
BoostHeads encourage you to look at their dyno graphs, consider
their achieved performance times and - if you're still sceptical - you can go
for a ride in a car equipped with the ESC-400. So long as you're in the vicinity
of Miami, Florida... "We are absolutely confident that, like everyone who has
taken us up on the challenge, you will walk away a believer."
Check out all the details of the ESC-400 at www.boosthead.com
is another electric supercharging device you may have seen on the market - the
Twin Turbo Zet. This unit contains two small PC-type fans and costs around
"The Twin Turbo
Zet" for our product review.
"Turbodyne Technologies Inc. is a leading engineering company
in the design and development of charging technology to enhance the performance
of internal combustion engines."
The Turbodyne Dynacharger is an electric assist device that can
be adapted to specific turbochargers. The Dynacharger system
comprises an electronically controlled ultra high-speed brushless electric motor
that's mounted between the turbine and the compressor of a conventional
turbocharger, together with an electronic power and speed control system.
Electrically, the operation of the Dynacharger alternates
between Motor Mode and Generator Mode. In Motor Mode, the Dynacharger provides
the desired boost pressure for low speed engine acceleration. In Generator Mode,
the Dynacharger utilizes the otherwise wasted surplus exhaust gas energy by
using the turbine to drive the electric rotor. At full engine power, the
generator can be used to slow the turbine, and in many cases alleviates the need
for a wastegate.
The most obvious benefits are improved transient response,
boost pressure available at low rpm and low load and greater turbo sizing
flexibility - you can rely on the Dynacharger for low-end boost and you can opt
for a huge compressor for strong top-end performance.
See the Dynacharger at www.turbodyne.com
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