 What
do you get when you take a smog choked British
sports car, put it on a diet and quadruple the
horsepower! You get the "Fastest Gun In The
East!" A electric car that is fun to drive, has
unbelievable performance, and is cheap to
operate and maintain! A car that can autocross
with the best, and serve as a poster car for
cleaner air!
Built by North Johnston High School students
in Kenly, NC this car was designed for
participation in the Carolina Electric Vehicle
Challenge. This car proves that electric cars
don't have to be slow, difficult to drive or
ougly! Competing against high schools from
across the southeast US, the Spitfire was
recognized at the competition as being the best
designed and constructed vehicle there, and on
the autocross track clearly dominated the
competition!
The car is owned by Pat and Ralph Goodwin.
Their antique car insurance agency, Classic Car
Services Inc. sponsored the car in the
competition so afterwards they would have a
unique car that they could use to promote their
business at shows and autocross events across
North Carolina.
This story documents the work that the
students did on the car. You can also find
technical design information about the car and
the components that went into the
conversion.
Where
every project starts...Thinking about
it!
One might say this was the view that
got me in trouble! I work for a electric utility
and manage our electric vehicle program. As part
of my responsibility I work with high school
students who learn about electric vehicles, even
building their own conversion. Many times as I
lifted the hood on this Spitfire, I thought
about how easy it would be to convert to
electric power. Lots of places to place
batteries. Particularly the smaller high
performance absorbed glass mat batteries, such
as Genesis Hawkers. The fact that someone had
long ago removed much of the required smog
equipment made this car a interesting candidate
for conversion!
Removal of the radiator clearly showed room
for batteries. Common sense cautioned about
placing too much lead ahead of the front axle,
but that's something the students will have to
figure out!
Other places to put batteries include the
previous gas tank location. The gas tank
location is on the shelf visible between the two
wheel wells. Batteries can go in front of, on
and behind this shelf. Again, one of the tasks
the students will have is to optimize battery
location to achieve the best weight
distribution.
Taking
it apart!
To start we weighed the car. Then we
pulled the engine, and body tub. All this was to
enable us to get to the frame. All the
suspension components are removed, examined and
replacements ordered as needed.
The front
cross member is being modified to allow room
for the ADC electric motor. This modification
will allow the motor to be mounted low in the
frame, thus helping to keep a low center of
gravity. A little more sanding and the students
will have the frame ready. The modifications to
move
the cross member forward to allow proper
mounting of the motor is complete. This
modification will make sure that the proper
driveline alignment is maintained.Front
suspension components have been cleaned,
repaired and primed, ready for painting, new
bushings, etc and reassembly.
 Here
it is! The motor attached to the overdrive
transmission. As you can see we have used a
special adapter plate. What you can't see is
that this adapter lets us use the original type
clutch!
No, we aren't going to use ordinary
batteries! Here is one of the Hawkers that will
provide the energy to propel our project!
How can you not get excited at this point!
Kevin Boykin, lead instructor on the project
checks everything out. Mr. Boykin is recognized
as being one of the best in the southeast US at
converting a gas car to electric power!
Getting
close!
Here you can
see the motor mounted in the frame and the
front battery box in front of it. The front
battery box has four of the Genesis batteries in
it. The four batteries weigh about 135 lbs. The
students were able to put the battery box
between the frame rails without interfering with
the front sway bar mounts or the steering rack.
Click
here to see the bottom of the front battery
box.
Check out the Carrera
shocks supplied by TSI Automotive! These
shocks, the Yokohama autocross tires, and the
camber compensator on the rear should help to
keep all 4 tires firmly planted on the autocross
course!
The four batteries up front aren't nearly
enough, so there are 9 more that will sit behind
the seat! This battery box will be power vented
outside of the car. 165 pounds over the axle and
about 135 in front of it! The students wanted to
keep weight distribution as close to stock as
possible, so no batteries in the trunk! The
thirteen total are fine for autocrossing but
would not last for extended driving. More
batteries were needed. We decided to add
DEKA
8G22NF batteries and mount them in a small
trailer. The trailer is designed to be pulled
behind a motorcycle. A nice light-weight,
removable solution.
Main
Electrical Components
Motor: Advanced DC 203-06-4001A
The brushed series DC motor is the best
overall motor for affordable road-going
conversions available today. AC motors operate
at high rpm that have to be stepped down, and
have expensive and complex speed control
systems. Brushless DC motors also require
expensive controllers. Permanent magnet motors
are very efficient, but only in a very narrow
rpm band, and quickly lose their efficiency in
the varying speeds of normal driving. Shunt and
compound motors are more expensive to build and
have poorer acceleration than series motors. For
these reasons, the brushed series DC motor is
the motor of choice.
Motor Ratings
It is not accurate to refer to a "10 hp
motor" or a "15 hp motor", because horsepower
will vary with volts and amps, and peak
horsepower will be much higher than the
continuous rating. It is also confusing to
compare electric motors to gas engines, since
electric motors are given a continuous rating
under load, and gas engines are rated at their
peak horsepower unloaded.
The motor weighs 107 lbs. and was mounted to
the Spitfire Overdrive Transmission. The
students originally tried to use the original
type clutch but found that it couldn't begin to
handle the increased torque and horsepower.
After locking the clutch plate to the pressure
plate assembly, the students found the car had
ample power to pull from a standing start in any
gear, reducing the need to change gears! When
autocrossing the car it is usually run in second
or third gear.
Controller: DCP Raptor 1200
The motor controller used employs a
microprocessor based control system (blue box in
figure 5). It provides high average currents at
low throttle positions, delivering exceptional
acceleration! Input from the battery pack is 156
VDC, with peak output at 1200 amps.
Batteries: Hawker Genesis 42Ah
There are 13 of the Genesis 42Ah batteries
for a total of 152 volts. These batteries are
distributed through the car to maintain proper
weight distribution.
Model G42 Length 7.775"
Width 6.525" Height 6.715"
Weight 32.9 lbs Total Weight 427.7 lbs
Preparing
The Car For Autocross Competition
Part of the Carolina EV Challenge
includes a autocross competition. Needless to
say, significant bragging rights go to the
quickest car between the cones!
 The
Triumph Spitfire has a past that was hard to
beat! In SCCA competition is finished top in its
classes for many of the years the car was in
production. But how would it do configured as a
electric vehicle? How well would it compete with
newer conversions?
Of course key to success was rebuilding
everything with modern day components. This
included poly bushings all around and a complete
rebuild of the braking system. Carrera
competition shocks were added all around and
Carrera springs were added up front. To help
control the rear end a Curry Camber Compensator
was installed. Finally a set of Yokohama
autocross tires were added!
Handling is unbelievable! The
car runs like its on a wire!
For
more information, visit the
websites:
North
Johnston High School, Kenly N.C.
Carolina
EV Challenge
Electric
Vehicles of America
TSI
Automotive
 Return
to Swaps Index
|
