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By
Peter Treydte
Gale
Banks Engineering Cummins Common Rail Product Evaluation
There
is no doubt that Cummins has established itself as the benchmark
of durability in the diesel pickup
truck marketplace.
Since 1989, the 5.9L power plant, commonly referred to as the
"B" engine,
has been the workhorse that Dodge has used to establish a foothold
among diesel enthusiasts. The engine has remained basically
the same over those years, with changes to the cylinder head
and the fuel injection system being the most significant updates.
Today, the fuel injection system is fully electronically managed,
providing the greatest level of control over fuel injection
dynamics to date.
MORE
POWER
When the task becomes how to achieve more power, the equation
is simple: power is increased by delivering more diesel fuel
to each cylinder during the power stroke, and achieving a
complete burn to harness the full measure of power potential
in the
fuel. Fuel delivery may be enhanced in one or more of three
methods: increase the fuel delivered by lengthening the injection
pulse; increase the pressure of the fuel, thereby increasing
the amount delivered; or change the timing of the pulse,
effectively improving the point of peak pressure in the
cylinder.
While
the problem statement is simple, the methodology is somewhat
complex. This is due in part to the advanced
nature
of the
engine electronics. As technology improves, certain checks
and balances are built into the vehicle’s electronic
systems, ensuring that the multitude of sensors and reacting
components are fully functional. That means that the addition
of "foreign" electronics intended to retune the
engine may throw up warning flags, commonly referred to
as trouble codes. At best, this is a nuisance, and at worst
it can cause the engine to run in a detuned, "limp-home" mode.
Thus the problem statement for development of any electronic
fuel enhancement device must include an interface that does
not cause a failure mode.
FUEL
TUNING
There are two aspects of fuel tuning that are worth focusing
on with the Cummins ISB common rail engine. The first is
fuel pressure. Because a common rail system by nature feeds
fuel
pressure to all the injectors through the same system,
fuel pressure can be raised throughout the system by recalibrating
the pressure pump’s output. But there is a limitation.
Seals and other components in the system are designed to
handle up to about 27,000 PSI, yet the system can be altered
to produce
pressures higher than that. Banks engineers determined
that under most operating conditions, pressures should
not exceed
24,500 PSI.
Injection
timing is another key tuning parameter that can yield tremendous
gains in power. In order to recalibrate
timing,
the electronics must be able to intercept vital engine
timing signals from the crankshaft and the camshaft,
and tune fuel
injection timing based on those signals. Once again,
certain limitations apply and must not be exceeded in order
to
safeguard the engine from harmful timing parameters.
DRIVETRAIN
SAFEGUARDING
Anyone who is familiar at all with Dodge Cummins pickups
knows that the potential weak link in the chain is
the automatic transmission. The 47RE, and its replacement,
the 48RE, have
grown from a design that was simply never intended
to
handle the extreme amount of torque that the Cummins
engine is
capable of delivering. If too much torque is applied
under certain
high load conditions, it is possible to cause the clutches
in either the torque converter or the transmission
itself to
slip. When this happens, power is not being transferred
from the engine to the rear wheels, no matter how much
the engine
might be producing. Prudent engineering incorporates
a method to protect the transmission from sustaining
damage
due to
added power.
EVALUATING
THE MASSES
A test cycle at Banks is only complete when it includes
testing of competitive products. Although the ISB
common rail is fairly
new to the market, there are always companies that
rush their product into the game—sometimes
with poor results. The area of greatest concern that
Banks engineers identified was
the claim by many manufacturers to have the aspect
of injection timing control dealt with. Research
revealed that while many
companies claimed to control injection timing, some
experienced problems with the feature resulting in
trouble codes and limp-home
conditions, forcing them to pull their product from
the market. Others simply claimed they had the feature,
but clearly did
not. This was obvious based on the fact that no interface
with onboard camshaft and/or crankshaft signals existed
in their
product.
In
some cases, a device may have offered extreme levels of power,
but it was clear that no
consideration
was
given to
fuel pressure limitations. Power was achieved by
applying massive amounts of fuel pressure.
It
is also quite clear that most manufacturers give no consideration
to the durability of the engine
or the
transmission. Exhaust
gas temperature is a limiting factor for any diesel
engine. Rampant overfueling of a diesel can result
in damage
to the internal components. Transmission slippage
was also
entirely
ignored by all products available. THE
CREAM OF THE CROP
Having established a solid problem statement, and
further clarifying the task at hand with competitive
evaluation,
the Gale Banks
Engineering staff set about designing a device
to create a new standard. The result is the Banks Six-Gun
Diesel
Tuner, the most advanced fuel enhancement product
available for
the
Dodge Cummins common rail. They then went one step
further by developing a competition-only optional
enhancement, the Speed-Loader™. Because the durability
of the engine
and transmission
is a prime consideration, the Banks engineers developed
a suite of features that adjust the fuel rate of
the engine according
to prevailing conditions. Dubbed AutoRate™, these
features constantly monitor various conditions
and
provide ActiveSafety™ to help
safeguard the drivetrain. Here is a list of features
and benefits:
Horsepower - The
Banks Six-Gun offers up to 105 additional horsepower
at the rear wheels, and
the
addition of
the Speed-Loader increases
output to 126 hp over stock.
Torque - Six-Gun increases torque output at the rear wheels by 258
lb-ft, with the bulk
of the
gains in
the very
useful lower RPM register. The Speed-Loader
increases rear wheel
torque to 290 lb-ft over stock.
Adjustable
On-The-Fly - Banks Six-Gun offers 6 distinct power levels,
from no
added power, to maximum available
output.
A dash-mounted rotary knob allows full access
to all levels while
driving for ultimate versatility.
Stacked
for Power™ - The Six-Gun increases fuel pressure, within the
determined
capability of the fuel system.
At every level
except Level 6 with the Speed-Loader option,
fuel pressure is kept below 24,500 PSI. Level 6 with
the Speed-Loader
keeps fuel pressure just below 27,000 PSI, the
maximum allowable
pressure for the system. Timing is also recalibrated
for optimum power output. Some competitive products
only offer
one or the
other of the two features mentioned. Therefore,
some consumers find it necessary to purchase
multiple devices and "stack" them
to achieve their desired power output. The Banks
Six-Gun is already stacked for power in a single
device, eliminating the
need for the added expense of multiple units.
Temperature
Limiting Control - Exhaust gas temperature is
the most vital statistic known for common usage
of a diesel
engine.
Speed-Loader adds fuel-limiting control based
on temperature measurement. (Note: For maximum performance,
Banks
always recommends improvements to airflow when
enhancing fuel
delivery.)
Transmission
Slip Monitoring - In order to monitor slip in the 47RE and
48RE transmissions, it is
necessary to have
electronics
that can "learn" the gear ratios
of the vehicle. The Six-Gun goes through an
initial learning mode to calibrate
itself to the vehicle, so that slip can be
detected either in the torque converter clutch
or in the
transmission clutches.
Generally speaking, 5% slippage is considered
to be the maximum allowable limit. Once the
Six-gun detects 3% slippage, power
is reduced to guard against damage from slippage.
Torque
Converter Clutch Engagement - The point in time when the torque
converter is most susceptible
to damage
is during
its initial engagement of the clutch. If
excessive power is being applied while the clutch is
engaging, slippage
will occur.
By sensing the engagement signal of the clutch,
the Six-Gun can momentarily reduce power
until the clutch
is fully
engaged, and then reapply power.
FMEA
Design - An
ActiveSafety feature, Failure Modes
Effects Analysis (FMEA) is Banks’ uncompromising design process
to ensure that the Six-Gun electronics will in no way
impact the durability or function of the onboard vehicle
electronics. In addition, the Six-Gun constantly monitors
its own inputs and outputs to ensure proper function.
ADDED
VALUE
The result of Banks’ diligence and attention to detail
is added value. Banks puts the extra effort
into identifying all aspects of the engine’s capabilities
and limits to give the consumer a feeling of confidence
when using the product.
The Six-Gun Diesel Tuner is packed with
features that no competitor can duplicate at the same price.
The
Six-Gun
with Speed-Loader
offers more horsepower and torque at the
rear wheels than is claimed by most competitors, often
at a lower price and always
with more built-in safety. |
