LS-1 in a Grand National
Robert Smith from Orange, Texas
found this Buick Grand National and just had to have it.
He wanted the Grand National because it had a performance
suspension where as the Monte Carlos do not. The only problem
was that the engine and transmission had a lot of miles on them
and needed to be rebuilt. Robert’s wife owns a LS-1
Camaro and he really likes the performance and drivability that
the LS-1 offers, so rather than rebuild the V-6, he chose to
install the LS-1 and 4L60E transmission. Robert took the car to
Street & Performance where Mark Kincaid performed the
transplant.
The LS-1 with a 4L60E transmission
attached was lowered into the engine compartment to check motor
mount and transmission mount placement along with oil pan
clearance. It was necessary to remove the oil pan to set the
engine into position. This told us right off that we would need
to replace the oil pan with a S&P modified pan and pick-up
tube. With the engine in place Mark found that he could use the
V-6 engine stands by changing them from side to side and
redrilling the bolt holes. A set of 305 V-8 Monte Carlo stands
will also work. Both type of engine stands use the
S&P motor plates.
Street & Performance offers these
LS-1 motor plates that allow you to use the original V-8 motor
mounts to place the LS-1 into the proper location. The plates
come complete with all mounting bolts and are available in
natural, polished and chrome. The plate kit does not include
the rubber motor mount.
The Grand Nationals 200R4 cross member
was modified to bolt to the 4L60E and notched for dual exhaust.
Next S&P custom modified the original LS-1 Camaro oil pan
and pick up tube to clear the front cross member. This oil pan
and pick-up tube are now part of S&P’s complete line
of oil pans which are offered on an exchange basis or out right
sale. A truck pan, windage tray and pick up tube can also be
used.
Installing the S&P manual speedometer
tail housing kit to be able to use a manual speedometer and
have the electric vehicle speed sensor which is needed for
shifting the 4L60E transmission.
‘96-up 4L60E 6 bolt to
4 bolt tail housing adapter for manual speedometer. Gear ratio
and tire rollout is needed when ordering.
The Grand National already had a high
pressure in tank fuel pump, but if you have a Monte Carlo or
other vehicle that had a V-6 throttle body, you would need to
change the intake pump to an AC DELCO EP-241. This is because
the throttle body only uses 20 lbs of fuel pressure where as
the LS-1 needs up to 58 lbs of pressure. Late Monte Carlos that
had the 305 carburetor engines will need to use an intake fuel
pump assembly (GM # 25092742) that will drop right into the
tank, as well as the AC DELCO EP-241. All of these G body cars
already have the return fuel line needed for the LS-1 Injection
system.
Factory Corvette accessories
configuration
Factory Camaro/TA accessories
configuration
1.Corvette Balancer
2.IROC/TA Balancer
3.C/K Truck Balancer
Should have a new tightening bolt when
replacing balancers. Tighten to 110 ft lbs. Then back off bolt
one turn. Retighten to 35 ft lbs and then turn bolt a
additional 140 degrees
The factory Camaro/TA accessories
configuration will not allow the alternator to clear the
Nationals G body steering gear box and the AC Compressor would
not clear the passengers side front cross member. The factory
Corvette accessories configuration also will not let AC
compressor clear the passenger side front cross member and the
power steering pump will not clear the upper A-Frame. The 5.3
and the 6.0 Truck accessories should clear, but the Camaro
balancer is 3/4” longer that the Corvette and the truck
is 1 1/2” longer. With all this to consider, it was easy
to choose the S&P Vette style bracket kit.
Since this car will be driven allot,
Robert opted to use chrome brackets and accessories for the
ease of cleaning. When installing the brackets or any other
accessories where two different types of metal come into
contact with each other, S&P highly recommends using an
anti-seize compound on all bolt threads. This will prevent
electrolysis that causes galling or seizing.
LS-1 oil pressure manifold. Vettes comes
with factory sending unit, but must be replaced with your gauge
sending unit. IROC/TA and others have to be drilled and tapped
to accept your oil pressure gauge sending unit.
You must install the original V-6 or 305
oil pressure sending unit into this location and extended the
original wires to the sensors to make the original instruments
read properly.
The 12mm plug located at the rear of the
passenger side head can be removed to provide a location to
install the Grand Nationals coolant temp sensor with the
original harness plug attached to it.
This will
provide the proper signal to the coolant
gauge. The head will have to be tapped for a pipe thread.
LS-1 G- Body Headers (Monte Carlo Style)
All Street & Performance Headers have
Stainless Steel Head Flanges and Collector Flanges for
better gasket sealing. Headers come
complete with Street & Performance special design gaskets
which have a thin layer of metal between the material and
collectors with oxygen sensor buns already installed. The front
oxygen sensors are required to control the fuel air ratio. The
rear oxygen sensors are needed for emission purposes.
All headers are available in plain steel
or thermal
coated inside and out.
