In our February 2012 issue we covered the basics on various types of power adders and introduced you to Magnuson Superchargers, their facility and our new supercharger. We wanted a Magnuson supercharger for the Maulin’ Magnum to take advantage of a positive displacement supercharger’s “area under the curve.” For our purposes we’re defining a positive displacement supercharger as a roots, hybrid roots, or screw type unit. In the Magnuson’s case, it’s technically a hybrid roots design.

Area under the curve refers to the total area under the power curve on a dyno chart. Turbochargers and centrifugal superchargers build boost in direct proportion to RPM which leads to a power curve that resembles a ski slope from idle to peak power. Positive displacement superchargers tend to have power curves that look more like a flat mesa top with a steep cliff leading to it in the lower rpm range. In other words, at low rpm they make more power and torque.

Given that the Magnum is heavy at
4,400 pounds with full interior,
a quarter tank of gas and our
own Alex Rogeo sitting at the
wheel, getting the car launched
is a bit of a challenge. If you
read our two-part write up
of our rear-end build up
(December 2011 and
January 2012) then
you know that the
steepest gears
you can get for
a 215mm pre-
2009 SRT axle
housing are
Richmond
3.55 gears.

For pure
quarter mile
use, we’d
really want
about a 3.90
rear gear set to
put us at just about
redline in forth gear at the
finish stripe. But since, A, they
don’t make that, and B, we have to
drive the car on a daily basis, 3.55s it is. So
between heavy weight and under gearing, we need all the
power and torque at low rpm that we can get.

The heart of the Magnuson supercharger for late model Hemis is an Eaton Twin Vortices Series (TVS) 2300 roots-type supercharger. Eaton is a large company with extensive experience providing superchargers to auto manufacturers. The OEMs have high standards for low noise, efficiency, and durability, which is good for us.

The TVS 2300 incorporates two four-vane rotors that are “twisted” into a 160 degree helix. The Magnuson Supercharger for 6.1L Hemi engines is fully 50-state legal and carries a C.A.R.B. sticker and EO number. Nice.

A tale of two rotors, on the left a four lobe straight rotor, on the right the same
four lobe rotor “twisted”
into a 160 degree
helix, as used in
the TVS 2300.
One of the tricks
on the new
gen TVS
supercharger
that reduces
noise and
increases
efficiency.