Downloaded from www.Manualslib.com manuals search engine The Northstar engine is designed to require less maintenance than many
other DOHC
V-8 engines. Engine systems are designed to remind the
driver when service is required.
An oil life index indicator monitors
ongoing operating conditions and reminds the driver when an oil change
is needed.
A low coolant warning message keeps track.of the level of this
vital fluid. Direct acting hydraulic tappets provide maintenance free zero
lash operation
of the 32 valves from idle to the 6500 rpm redline. The
camshafts are driven by
a two stage roller chain assembly which is
designed
to provide quiet maintenance free Operation. Platinum tipped
,spark plugs increase the replacement interval
to 100,000 miles.
The four valve per cylinder design provides more efficient engine
breathing which results in higher power than comparable
two valve
engines. The central location
of each spark plug ensures a fast and
complete burning of the fuel/air mixture. The induction system uses
smooth thermoplastic tubes to channel air into the cylinders. The
smoothness
of the tubes is equivalent to the elaborate port polishing
methods used for race car engines. Careful design using the shape and
length
of the tubes boosts horsepower by using sonic pressure waves
created by the motion
of the inlet valves to increase the amount of air
entering ,each cylinder.
The Northstar engine is also designed
to be very durable. The aluminum
block has cast-in-place iron cylinder liners for greater wear resistance.
High strength connecting rods support the free floating piston pins in
bronze bushings for superior high speed performance. The fillets
of the
nodular iron crankshaft undergo
a high pressure compression rolling
operation to improve their resistance to fatigue.
Quiet operation is enhanced by the use of special materials and designs.
The front cover of the engine is stamped from laminated steel which
damps out noise. Special cam cover gasket seals isolate valve train
operation.The fuel injectors are placed inside the induction system
housing
to eliminate- the clicking noise which is common to other fuel
injected engines.
The Northstar engine is designed to provide years of efficient. reliable.
satisfying operation.
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320
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The power rack and pinion..stee&g .gstem--h,w, a ,rotaq- spool valve which
directs hydraulic fluid coming from the power steering pump .to one side or
the other
side of the rack piston. The integral rack.piston is attached to the
rack. The rack piston converts hydraulic pressure to a linear force which
moves the rack4eft or right.
The force is then transmitted through the
inner and outer tie rods to the steering
.. knuckles, , which turn the wheels
If hydraulic assist is not available, manual conirol, is ‘maintained. However
under these, conditions. more steering effort is required.
4.6 LITER NORTHSTAR ENGINE
Displacement ............................... .4.6L (279 cu.in.)
No. of Cylinders
................ 32-valve DOHC 8 - 90 Degree V
Power (ACC. to
SAE 51349) ................ 270 (b,hp) @ 5600 rpm
Torque (ACC. to
SAE 51349) ............ 300 (lbs. ft.) @? 4000 rpm
ELDORADO
...................................... 204 (kW) @ 5600 rprn
...................................... 407(N*m) @ 4OOOrpm
ETC
Power (ACC. to SAE 51349) ................ 295’(bhp) @ 6000 rpm
Torque (ACC. to
SAE 51349) ............ 290 (lbs. ft.) @? 440.0 rpm
Bore
........................................ 93mm.(3.66.in.)
Stroke
...................................... .84mm (331in.)
Compression Ratio
.................................... 10.3: 1
Cylinder Block ...... Die Cast Aluminum with Iron Cylinder Bores
Cylinder Heads
................................. Cast Aluminum
Intake Manifold-
............ Die Cast Magnesium / Thermoplastic
.......................................... Air Induction Tubes
........................................ 220 (kW) @ 6000 rpm
...................................... 393 (Nom) @ 4400 rpm
Valve. System ................... Direct Acting Hydraulic Tappets
Intake Valve
.................................. 33mm (1.29 in.).
Fkhaust Valve,. ................................ 29mm (1.14.h.)
Pktons
...................................... Cast Aluminum
Firing Order
.................................. 1-2-7-3-4-5-6-8
Left Bank ........................................... 2-4-6-8
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