Cellular
phones are now available that are almost as small as a credit card.
Slim, lightweight televisions can be hung on your wall, and now
late '90s technology is bringing us extremely powerful, lightweight
ignition systems that can fit in the palm of your hand and are designed
to fit conveniently under the hoods of vehicles with limited space.
We watched as Steve Cole of The Turbo Shop (TTS) in Compton, California
installed one of these new high-tech ignition systems from Crane
in a late-model, LT1-equipped Z28 Camaro. Although this Crane ignition
system is a superior replacement for stock ignition systems, this
Camaro uses an Accessible Technologies ProCharger intercooled supercharger
making 7 pounds of boost. This allowed Cole to also add Crane's
HI-6TR timing-retard control unit and 9000-0110 boost sensor. The
timing control allowed Cole to program more timing into the engine
through the computer for better performance under low boost and
also allows the Crane timing control to pull timing out when the
engine is under boost to avoid detonation. In performance capability,
this system is equally at home on the street or at the racetrack.
The ultimate goal of in ignition system is total
ignition of the air/fuel mixture in the cylinder. There must be
enough voltage at the spark plug to jump the gap, but after that
the current and the spark duration do the work to ignite the fuel
mixture. Elements such as Spark energy and spark duration are the
important factors.
Spark energy does the work of igniting the air/fuel
mixture. The Crane HI-6S ignition's maximum energy output is 50
percent higher than that of OE systems (70 percent higher with the
Crane PS91 coil). Spark duration is how long the spark sequence
occurs. The HI-6S fires for 20 degrees of crankshaft rotation. This
20-degree-duration spark sequence ensures that the air/fuel mixture
is ignited and completely burned. The Crane HI-6S ignition generates
multiple sparks at low rpm and a long, high-energy spark at high
rpm as added insurance to completely ignite the fuel mixture, resulting
in increased engine efficiency, easier starting, greater power out-
put, and less lean surge in street performance vehicles.
The
HI-6S also includes a two-stage rev limiter that can be set via
rotary trimpots. The adjustment range is 1 ,000 to 5,000 rpm for
stage limit and 3,000 to 7 ,000 rpm for maximum limit. At the rev
limit, all cylinders are fired in an optimum sequence that greatly
reduces engine and drivetrain stress. The lower rev-Iimit stage
can also be used as an antitheft function by wiring it to a switch
hidden under the dash. This switch is used to select a very low
rev limit that keeps the engine from running above idle. The HI-6S
is compatible with most '81-and-Iater cars and '86-and-Iater light
trucks with distributor ignitions and computer engine control. It
does all this in a compact unit that measures only 5 inches long,
3 inches wide, and 1 inches high and weighs only 11/2 pounds.
You can mount the HI-6S anywhere you like within
reach of the Crane wiring harness. Cole mounted the HI-6S just behind
the driver-side headlight assembly on the engine side of the radiator
support (as far as possible from engine heat sources). Four screws
attach the unit to any panel.
The Crane PS91 high-intensity ignition coil offers
up to 70 percent greater energy at the spark plug. It's an E-core
design with a closed magnetic path, which gives improved energy
transfer to the spark plug. The PS91 also features solid epoxy encapsulation,
a heavy-duty metal bracket for ultimate resistance against severe
shock and harsh vibration, and a high-tension tower for improved
coil-wire retention and a longer creep path to protect against high-voltage
arcing.
Again,
you can mount the coil any-where you like within the reach of the
Crane wiring harness. Cole custom- made a bracket to mount the coil
neatly to the supercharger bracket.
Timing-retard capabilities can be added via the
optional HI-6TR timing-retard control. The HI-6TR adds 0 to 20 degrees
adjustable timing retard and features a status LED that illuminates
when retard is being applied. The LED can be mounted neatly under
the dash.
The HI-6TR can also be used with Crane's boost sensor
for boost-proportional retard for turbo/supercharged applications.
When the boost sensor is connected, the retard setting on the Timing
Retard Control then refers to a retard slope from a to 4 degrees
per psi of boost. You simply divide the knob setting by 5 to determine
the retard slope. For example, if the knob is set to 5 degrees,
the retard slope is 1 degree per psi, and at 5 psi of boost the
retard is 5 degrees. As boost rises further, the retard increases
at this same slope up to a maximum of 20 degrees.