2.3L High Output Quad 4 Training Series (part 1)

The new High Output Quad 4 from General Motors
Truly a high-tech engine developed to meet and surpass
the performance, economy, and durability characteristics
of the world's best power plants
Available as standard equipment in the Chevrolet Beretta GTZ,
the high output Quad 4 is more efficient
at producing and torque
then nearly every normally aspirated
four valve engine on the market
Except for one BMW, one Ferrari, and one Lamborghini,
this engine is the most potent normally aspirated
power producer currently on sale in the U.S.
Standard GTZ equipment includes
a 5-speed manual transmission,
specific front, rear, and rocker panel treatments,
front and rear spoilers,
sixteen inch aluminum wheels, fog lights,
reclining bucket seats with four-way headrests,
Scotchgard fabric protection,
four-way tilt and adjustable lumbar seat support,
and leather wrapped sport steering wheel,
and gauge package with tachometer.
The most modern development and production
processes have gone into the creation of the
High Output Quad 4
In order to achieve its excellent fuel economy,
a host of the innovative design criteria were used
such as low friction, good combustion,
electronic fuel and ignition controls
and a high power to weight ratio
Special emphasis was given to designing an
engine that would deliver low-speed torque
a real challenge for a 2.3 liter four cylinder engine
The ability to produce an engine that would deliver
unparalleled levels of quality, reliability,
and durability came about after judicious
use of fundamental basic engine designs,
simple engine control systems,
unique manufacturing processes,
and an extensive validation program
Why the name High Output Quad 4?
Quad refers to it's inline four cylinder configuration
Four means that there are four valves per cylinder
With its chain driven double overhead camshafts,
the High Output Quad 4 boasts more
horsepower and torque than the standard
Quad 4 motor introduced in 1987
The High Output Quad 4 torque is rated at 180 hp at 6,200 rpm
It produces nearly 1.3 horsepower per cubic inch
which is an exceptional achievement for a production engine
By comparison the standard Quad 4 engine
has a 1.1 horsepower per cubic inch rating
which is itself a significant achievement
High Output Quad 4 torque is rated at 160 ft. lbs. at 5,200 rpm
another indication of this power plants capabilities
Redline is nearly 7,000 rpm
Combined with a compression ratio of 10:1,
this engine has many obvious
connections with racing technology
0-60 acceleration in the Beretta GTZ is 7.8 seconds
The valve train consists of two chain driven
overhead camshafts with direct acting lifters
The cylinder block is cast gray iron
The cylinder head, camshaft housings, oil pan, timing
chain housing, and several other components are aluminum
A single serpentine belt driven by the crank shaft
powers the generator and the air conditioning compressor
The power steering pump
is driven off the rear of the intake camshaft
and the water pump is driven by the camshaft drive chain
The engine is equipped with a front
mounted port fuel injection system
The High Output Quad 4's combustion chamber has a modified
pent-roof design that insures optimum combustion efficiency
Changes to the combustion chamber are only one area
that has increased performance on this power plant
The ram-tuned intake manifold runners
maximize volumetric efficiency
The manifold is made from lightweight aluminum
In order to accommodate the higher
cylinder wall and oil temperatures,
slots have been cast into the block between the cylinders
These slots allow coolant to pass
between the cylinders to cool the walls
The cast iron exhaust manifold is a 4-into-1 design
The oxygen sensor is mounted at the 4-into-1
connection, a position which permits it
to gather exhaust data from all four cylinders
This arrangement is designed to sense oxygen
content without affecting the tuning of the system
A two-piece heat shield insulates the exhaust
manifold for lower under hood operating temperatures
The speed density fuel injection system
uses a manifold absolute pressure or "MAP" sensor
One of the most innovative elements of the High Output Quad 4
is a manufacturing process called micro-sizing
This close tolerance process is used on the cylinder block,
cylinder bores, crankshaft bearing bores, and connecting rods
Micro-sizing not only produces the necessary finishes and
geometry needed to meet the low friction design goals
but it eliminates the need to selectively
fit these components in assembly
As a result, there are only single sizes for pistons,
main bearings, and connecting rod bearings
This is a major benefit should it be necessary to
replace these components in a customer's engine
One of the most innovative systems of the High Output Quad 4
is the ignition assembly cover
It serves many purposes in addition to dressing
up the appearance of the engine compartment
It acts as RFI/EMI suppressor and as a splash shield
Beneath this attractive die-cast cover you'll
find a distributorless ignition system
The ignition assembly cover also serves as a heatsink
for the ignition module
The cover is mounted on top of the
engine between the two camshaft housings
The ignition module includes
closed loop dwell control and
limited backup spark timing control
The ignition is a fast rise, two coil system
with the coils bolted to the ignition
assembly cover directly above the spark plugs
Secondary spark plug wires are not required because the
secondary conductors are contained in the shell assembly
Four connectors and boots on the
spark plugs correspond with the plug wires
found on conventional ignition systems