Heres an artical I found sometime ago that I thought was really good. I
forget where I got it from so I cant give credit but here it is.
NEW OR CHANGED
3800 Series III Supercharged 3.8L V-6 (L32)
2004 Model Year Summary
· New RPO for Pontiac Grand Prix
· Eaton Gen V Supercharger
· Returnless Fuel Injection
· Electronic Throttle Control
· Dampolator Vibration Balancer
· Powdered Metal Connecting Rods
· Ultra-Fast Oxygen Sensors
· PO5 Powertrain Control Module (PCM)
· Single Close-Coupled Catalytic Converter
· Improved Sealing
· Improved Accessory Belt
· Improved Starter
· 5W-30 Engine Oil
FULL DESCRIPTIONS OF NEW OR CHANGED FEATURES
NEW RPO FOR PONTIAC GRAND PRIX
With the launch of Regular Production Options L26 and L32 in the 2004
Pontiac Grand Prix, the acclaimed 3800 Series II 3.8L V-6 becomes the
3800 Series III. Objectives for the Series III were driven by the
customer, and straightforward: Improve quality, performance and
flexibility; reduce and noise, vibration and harshness as well as cost
of ownership; and deliver contemporary, high-tech features such as
Electronic Throttle Control.
Each has been achieved. Moreover, these objectives were achieved without
reducing fuel economy or increasing unit cost, while preparing the 3800
Series III for a near-zero emissions standard mandated for 2005. Bottom
line: The Series III enhances what was already one of GM’s highest-rated
engines in both brand value and customer satisfaction.
EATON GEN V SUPERCHARGER
The 3800 Series II SC is fitted with the most-sophisticated
supercharging technology available: the segment-exclusive Eaton Gen V
supercharger. So equipped, the 3800 Series II gives the 2004 Grand Prix
class-leading output and acceleration, with the overall “drivability” or
flexibility that sport sedan and coupe buyers expect over a broad rpm
The 90-cubic inch Gen V supercharger is very compact. Its housing
includes the throttle-body adaptor, crankcase ventilation plumbing,
coolant passages, the evaporative emissions purge valve and the rotor
drive mechanism. The drive mechanism is sealed and permanently
lubricated, obviating the need for oil connections and eliminating a
potential source of leaks. Moreover, the Gen V features all-cast
components and a larger, low-restriction outlet port. The tuned inlet
port is also less restrictive, compared to previous-generation
superchargers, allowing a larger (75 millimeter) throttle body. As a
result, more air is pumped by the supercharger through the Series III’s
induction system. The Gen V’s rotor is finished with Abraidbable Powder
Coating (APC) rather than epoxy. APC is a patented material containing
graphite that is electrostatically applied to the rotor and baked on. As
a result, the rotor requires less clearance within the supercharger
housing, resulting in less leakage around its edges, greater airflow at
a given operating speed and lower operating temperature. The Gen V’s
rotor bearings have been enlarged to increase durability and reduce
operating noise and vibration.
As a result, the Gen V operates at considerably higher efficiency than
its predecessors. At wide open throttle, the Gen V turns at 700 fewer
rpm (a 9 percent reduction), draws 13 percent less power from the
crankshaft, decreases operating temperature 15 percent and increases
volumetric efficiency 9 percent. For the customer, that means a 9
percent increase in horsepower (see product specifications), and best-
in-class acceleration times for the Grand Prix. Moreover, the 3800
Series III SC does not require premium fuel, and even with regular it
produces as much power as the Series II. A Grand Prix owner might use
regular for workweek commuting, then fill with premium for more
spirited, enthusiast-style driving on the weekend.
RETURNLESS FUEL INJECTION
The 3800 Series III is equipped with a “returnless” fuel injection
system that eliminates fuel return lines between the engine and the
Also known as a demand system, this new sequential fuel injection uses
Bosch EV-6 injectors. Previous 3800s used a return line to manage fuel
pressure by bleeding off excess fuel at the engine-mounted fuel rail and
returning the excess to the tank. The new system eliminates the return
lines and moves the fuel pressure regulator from the fuel rail on the
engine to the fuel tank. The fuel rail incorporates full-length pressure
pulse dampeners that reduce fuel injector induced pulsations, which in
turn improves fuel-flow distribution and reduces noise.
Because it delivers only the amount of fuel need by the injectors, and
returns no fuel to the gas tank, the returnless system essentially
eliminates heat transfer from the engine to tank. This reduces the
amount of vapor generated in the tank, and captured by the Onboard
Refueling Vapor Recovery (ORVR) system.
ELECTRONIC THROTTLE CONTROL (ETC)
The 3800 Series III SC features electronic “drive-by-wire” throttle
control. With ETC, there is no mechanical link between the accelerator
pedal and the throttle. A potentiometer at the gas pedal measures pedal
angle and sends a signal to the Throttle Actuator Controller (TAC)
module, which is integrated in the throttle body and passes the signal
to the Powertrain Control Module (PCM). The PCM then directs an electric
motor to open the throttle at the appropriate rate. ETC delivers a
number of benefits to the customer. It uses several data sources,
including the transmission's shift patterns and traction at the drive
wheels, in determining how far to open the throttle. ETC delivers
outstanding throttle response and greater reliability than a mechanical
throttle. Cruise control functions are integrated into the throttle
control, reducing the number of engine parts and simplifying assembly.
Further, ETC has been specifically tuned on the Series III to match the
sporting character of the Grand Prix. It is programmed with 19 separate
throttle maps, or curves, tailored to deliver engine response according
to the driving situation. At lower speed the curves are more
progressive, for more subdued engine response. During parking lot
maneuvers, for example, a given application of the gas pedal will
deliver less engine power. At medium to high speeds, the throttle curves
are steeper for more aggressive engine response.
Multiple throttle curves mean more immediate-and appropriate-engine
response over the full range of driving situations. The benefits are
most obvious over 20 mph, where the Series III’s ETC delivers power in a
much more linear fashion than a mechanical linkage, with immediate
response and virtually no peaks or valleys.
DAMPOLATOR VIBRATION BALANCER
The 3800 Series III features a Dampolator that combines the best
features of different devices designed to reduce torsional vibration in
Because of their cylinder configuration, 90-degree V-6 engines can
create torsional vibration in the crank-essentially flexing along the
length of the crankshaft-at certain engine speeds. Engineers have
developed various means of either damping or counteracting this flex.
One solution is a standard damper, or a mass (usually a pulley-like
disc) fitted to the front end of the crank with a thin rubber spring.
Dampers are effective controlling crank vibration at higher engine
speeds, typically above 4500 rpm. Another option is an isolator, which
uses a thick rubber spring on a tuned pulley to prevent low-speed crank
vibration from passing through the accessory drive belt to components
such as the water pump or air conditioning compressor. An isolator is
effective only at low engine speeds.
The Series III Dampolator delivers the benefits of both a damper and
isolator. This computer-tuned crank balancer consists of two separate
discs with two rubber springs of different thickness. It is effective at
both ends of the rpm range and as a result, reduces vibration and
harshness regardless of engine speed.
POWDERED METAL CONNECTING RODS
The 3800 Series III has new hot-forged powdered metal connecting rods.
Powdered metal is more durable and reliable than conventional cast iron,
delivering greater anticipated life. As importantly, the powdered metal
rods are stiffer than the cast iron parts they replace. That increases
the resonant frequency of the rod and translates to lower vibration
amplitude, meaning an overall increase in engine smoothness.
ULTRA-FAST OXYGEN SENSORS
The 3800 Series III is equipped with oxygen sensors with increased
heating capacity. The front sensor is rated at 8.5 watts and the rear at
7.5 watts, compared to 6 watts in the 2003 3800 Series II, allowing the
sensors to achieve their most efficient operating temperature more
quickly. The new sensors are also pulse-width modulated, allowing the
PCM to manage them at variable heating rates, rather than with a basic
The oxygen sensors are located where the exhaust manifold runners meet,
before the catalytic converter in the engine's exhaust stream, and after
the catalytic converter in the exhaust pipe. In effect, they measure
emission levels going into the catalytic converter and emission levels
coming out. Using readings from both sensors, the PCM manages various
engine operations in a fashion that minimizes exhaust emissions. The new
ultra-fast sensors allows the exhaust system to achieve this “closed
loop” operation in matter of seconds, effectively monitoring oxygen
levels before and after the catalytic converter for maximum emissions
PO5 POWERTRAIN CONTROL MODULE (PCM)
The new P05 PCM provides state-of-the-art electronic engine management
in the 3800 Series III. The PO5 has 50 percent more random access memory
(RAM) than the previous-generation P04, twice as much read only memory
(ROM) and a 60-percent increase in clock speed (approximately 25 Mhz).
It allows more integration of powertrain and vehicle systems, such as
electronic traction control and heating, ventilation and air
conditioning (HVAC) operation and it provides more sophisticated
diagnostics, particularly for the Onboard Refueling Vapor Recovery
(ORVR) system. Moreover, it takes full advantage of new features such as
the ultra-fast oxygen sensors and Electronic Throttle Control.
SINGLE CLOSE-COUPLED CATALYTIC CONVERTER
The 3800 Series III features a more efficient dual-brick, close-coupled
catalytic converter. This 1.3L converter is mounted near the engine
rather than under the vehicle floor, and it requires a flex-coil
crossover to join the downpipe on the front exhaust manifold with the
rear exhaust manifold.
The new design has several advantages. Because the exhaust ports and
exhaust manifolds heat more rapidly than any part of an engine, moving
the catalytic converter closer to the manifold in turn allows the
catalyst to heat more quickly. So positioned, the catalytic converter
achieves light-off-the temperature at which exhaust emissions are most
efficiently oxidized-more quickly. This considerably lowers emissions
during cold starts-a brief period when an engine operates at its highest
emissions level, and a critical phase in government certification tests.
Additionally, control enhancements mean the Series III catalyst requires
less precious metal. A combination of metals such as platinum, palladium
and rhodium in the catalytic substrate create the chemical reaction that
turns exhaust emissions into oxygen and water vapor. These refinements
reduce the overall cost of the converter.
DIRECT-MOUNT AIR CONDITIONING COMPRESSOR
The air conditioning compressor bolts directly to the 3800 Series III’s
engine block, without struts or braces. This direct mounting
considerably reduces vibration at the compressor and contributes to the
overall reduction in noise, vibration and harshness.
The 3800 Series III development team applied the latest sealing
technology whenever possible. Improvements start with the rocker cover
and oil pan gaskets, which are manufactured from an enhanced Elastomer
material. The new gaskets provide better bead sealing and are more
resistant to oil seepage for the life of the engine. Finally, the rocker
cover gaskets are designed to enhance the structural rigidity of the
covers, thereby reducing overall engine vibration.
Other gaskets were optimized with the same attention to detail. The
lower intake gaskets are manufactured from a new HNBR material, which is
more resistant than the previous silicone material to long-term
deterioration with exposure to engine coolant. These gaskets now have
compression limiters that maintain appropriate gasket compression for
the life of the engine.
IMPROVED ACCESSORY BELT
The accessory drive belt accommodates the new direct-mount AC
compressor. Supplied by Conti Tech, the belt is validated to the same
durability standard as that on the 2003 3800 Series II, but it was
specifically developed for quieter operation, further reducing
operational noise and harshness. The belt is manufactured of a new
“EPDM’’ rubber compound which resists hardening and cracking that
normally occurs with ozone exposure, extending the belt’s anticipated
life well beyond 10 years.
The 3800 Series III uses a new starter introduced in conjunction with
the switch to 5W-30 engine oil (below). This starter is validated to the
same durability and performance standards as those used on previous 3800
V-6 engines, and it weighs 2.5 pounds less, trimming an equal amount
from overall engine mass.
5W-30 ENGINE OIL
The recommended lubricant for the 3800 Series III is 5W-30 oil, compared
to 10W-30 in previous 3800s. With the lighter oil, the maximum change
interval does not change. GM’s industry-leading Oil Life Monitor still
calculates oil life based on a number of variables, including engine
speed, operating temperature, load or rpm variance and period of
operation at any given load and temperature, and then recommends a
change when it’s actually needed, rather than by some pre-determined
interval. The owner’s manual in cars equipped with the 3800 Series III
will continue to recommend an oil change at least once a year.
The change in lubricant was driven by efficiencies in the engine and
near-universal availability of the new GF-3 standard engine oil.
GF-3 uses a new refining process, and it contains a friction modifier,
meaning that that at a given weight or viscosity, it's more resistant to
breakdown with heat. The 5W-30 engine oil is more efficient in cold
ambient temperatures. It creates less friction or fluid resistance when
the engine is cold, requiring less cranking power and reducing fuel
consumption during cold starts. The 5W-30 oil also reaches its most
efficient operating temperature more quickly that 10W-30.
GM’s 3800 V-6 is to V-6 engines as the original Chevrolet small block it
to the V-8. Based on numbers produced and its enduring value and
functionality, the 3800 is the most significant V-6 ever designed. It
remains the benchmark for pushrod-actuated, overhead-valve V-6 engines.
The new Series III enhances the 3800’s reputation as a competitive,
contemporary engine, with output, efficiency and emissions levels that
meet or beat overhead cam engines, and superior low-end response.
The basic 3800 architecture dates to 1962, when the first version was
introduced in a Buick. Since then more 25 million 3800s have been built,
and it’s configuration and technology have constantly evolved. It
consistently rates highest for customer satisfaction among GM engines,
as determined by J.D. Power, and it has frequently been rated a Best Buy
by Consumer Reports. Both the enthusiast and business press have raved
about the 3800. It has been selected as one Ward’s Auto World’s “Ten
Best Engine in the World” three times in the last five years, and for
several lists of the best engines of the century published in 2000. The
3800 assembly plant in Flint, Mich., has been rated one of the most
efficient and up-to-date engine plants in the world.
The 3800 Series II V-6 was first supercharged for the 1992 Buick Park
Avenue Ultra. The result was output and performance comparable to
competitive V8s, with the efficiency of a V-6. The durable, highly
refined design of the standard 3800 allowed most major engine
components, including block, crankshaft and cylinder heads, to be used
for the supercharged variant without modification. The 3800 SC’s
acceptance by customers has meant steadily increasing application in
With launch of the new 3800 Series III, this 90-degree V-6 improves in
nearly every respect and adds contemporary, customer-driven technology
such as Electronic Throttle Control. Yet its basic strength hasn’t
changed. GM’s 3800 is the most successful V-6 ever because drivers care
more about quality, value and real-world performance than the specific
technologies that produce those traits.