Tons of General LS Information - oil pan, accessories, cyl heads, etc

LS SERIES CRANKSHAFT RELUCTORS AND SENSORS

LS based motors use 2 different reluctor rings and sensors (24x and 58x). There are also 3 different bolt patterns for the flywheel/flexplate : 6-bolt, 8-bolt and 9-bolt. Proper orientation of the crank ring is required if switching the reluctors. Below are photos of the orientation of the rings. You will notice on both rings, there are triangular/arrowed windows that align with 2 bolt holes, and the non-windowed portions of the ring cover the crankshaft throw weights. A 24x pickup ring uses a black colored crankshaft sensor, a 58x pickup ring uses a gray colored crankshaft sensor. The connectors are also differently keyed between the 2 sensors.

24X crankshaft ring installed
58x crankshaft ring installed

LS based engines use 1.7:1 ratio rocker arms, LS7 engines use 1.8:1 ratio rocker arms

LS GEN III SMALL BLOCK CHEVROLET CYLINDER HEAD CASTING #'S

CASTING #

10215339

12556743

12558806

12559863

12559853

12559862

12559895

12561706

12561873

12562317

12564241

12564243

12572035

USAGE

LS1

LS1

LS1

LS1

LQ4

LS1

LS6/LS2

PORT

CATHEDRAL

CATHEDRAL

CATHEDRAL

CATHEDRAL

CATHEDRAL

CATHEDRAL

CATHEDRAL

CATHEDRAL

CATHEDRAL

CATHEDRAL

CATHEDRAL

CATHEDRAL

CATHEDRAL

YEAR

97 CORVETTE

99 TRUCKS

97-98 CORVETTE/F-BODY

99-02 CORVETTE/F-BODY

99-02 CORVETTE/F-BODY

99-00 TRUCKS

00-07 TRUCKS

01-04 TRUCKS

99-01 TRUCKS

01-04 TRUCKS

00-04 CORVETTE/00-02 F-BODY

01-04 CORVETTE/ 04-06 GTO

01-04

CID

346

325

346

346

346

287/325

325

325

364

364

346

346/364

364

CC

67

61

68

68

68

61

61

61

71

71

68

65

71

INT

200

200

200

200

200

200

200

200

210

210

200

210

210

EXH

70

70

70

70

70

70

70

70

75

75

70

75

75

MAT

AL

AL

AL

AL

AL

AL

AL

AL

CI

AL

AL

AL

AL

LEGEND

AL = ALUMINUM HEADS, CI = CAST IRON HEADS

LS1/LS6 Cathedral port design
LS3/92 Rectangular port design
LS7 Intake Port

CATHEDRAL (LS1/LS6/LS2/LQ9/LQ4)

MLS (multi layer) head gaskets are compatible with LSx cylinder heads that have a flat deck surface (without a pocket)

RECTANGULAR (LS3/L92/L76/L99)

LS7

MLS compatible heads have a flat deck surface, and have no pocket.

LS SERIES GEN III INTAKE MANIFOLDS

98-00 LS1 Camaro/Firebird intake has hole and boss for EGR port
01-02 LS1 Camaro/Firebird, All Corvette models did not have provision for EGR
Truck style intake, has bosses for "Vortec" plastic cover, also has EGR on side

There were many different intakes used on the LS series motors. There are designs for each head style : cathedral port (LS1/LS2/LS6/4.8/5.3/6.0), rectangular port (LS3/L92) and LS7. There are also different style height intakes : car platform and truck platforms. You can interchange intakes as long as you use the same cylinder head design, and use the corresponding fuel rails, injectors and throttle bodies (as certain models have different bolt patterns).

THROTTLE BODY DIFFERENCES

  • There are 2 different mechanical throttle body arms. The photo on the left is the short arm, it can be easily recognized from the round collar. The photo on the right is the long arm, and the collar is straight. You must use either an adjustable throttle cable, or a throttle cable specific to that throttle body for the throttle to open properly.
  • There are also 2 basic throttle bodies : car and truck. The difference is the coolant passage for water pump clearance and the breather hose angle (for throttle bracket clearance)
98-99 LS1 Camaro, 99-03 LSx based Truck throttle body.  Uses short arm.
00-02 LS1 Camaro throttle body, uses long arm.

FUEL INJECTORS

Various GM fuel injectors
Fuel injector connectors

LS SERIES III VALVE COVER BOLT PATTERNS

Perimeter bolt valve covers have 9 bolts, all located on the outside perimter (top), while the ceter bolt valve covers have 4 bolts, all in the center (bottom)

Although there are many different valve covers for many different applications, there are basically 2 different valve covers : perimeter bolt valve covers, and center bolt valve covers. The perimeter bolt valve covers were used on 97-98 Corvettes and 98 Camaros and Firebirds. All other models used the center bolt valve covers. On the perimeter bolt valve covers, the ignition coils bolt directly to the valve cover. On the center bolt valve covers, the ignition coils bolt to a bracket, which in turn bolts to the valve cover. This is to facilitate the removal of the valve cover when necessary.

LS SERIES III VALVE COVER BREATHER DIFFERENCES

Valve covers differ in breather location, as well as angle of the filler tube/PCV location
Valve covers differ in breather location, as well as the breather locations.

There are many different model valve covers, all specific to each application, but for swap purposes, you can get around having the exact cover. All the LS models have the oil filler on the passenger valve cover (except LS7). Breather locations (the small tubes on the outside of the covers) differ between models for intake purposes, however, they are all just breathers.

LS SERIES GEN III FRONT DRIVE CONFIGURATIONS

98-02 LS1 Camaro & Firebird front drive setup
97-04 LS1/LS6 Corvette front drive setup
04-06 LS1/LS6 CTS-V front drive setup

98-02 LS1 CAMARO & FIREBIRD

97-04 LS1/LS6 CORVETTE

04-06 LS6 CTS-V

04-06 GTO LS1/LS2 front drive setup
99-07 1500/2500 4.8/5.3/6.0 Truck front drive setup
05-07 LS2/LS6 Corvette front drive setup

04-06 LS1/LS2 GTO

99-07 4.8/5.3/6.0 TRUCK

05-07 LS2/LS7 CORVETTE

LS SERIES GEN III HARMONIC BALANCERS

3 different LS-based balancers, from left to right : Corvette/Cadillac, Camaro/Firebird/GTO, Truck

There are basically 3 different harmonic balancers that effect belt spacing : (1) Corvette and Cadillac (car), (2) Camaro/Firebird and GTO, (3) Truck series and SUV. As you can clearly see, the distance between the crankshaft end and where the belt rides are different in all 3. All of the LS based balancers are neutral balanced, and can be installed on any LS application as long as the same platform accessories are used.

LS SERIES GEN III WATER PUMP PULLEY DRIVE LOCATIONS

LS1/LS6 Corvette water pumps have the wide pulley and the belt rides close to the pump,
Picture showing that 2 belts can be used at the same time and that the water pumps are interchangeable between platforms.
Camaro/Firebird and GTO water pumps also use the wide pulley, and the belt rides close to the edge of the pulley.

The Corvette, Camaro, Firebird and GTO all share the same water pump, even though they use different depth balancers. The reason the water pumps are interchangeable is that the water pump drive pulley is twice as wide as the other platforms, allowing the belt to ride in 2 different locations. Therefore, you can use either water pump with either platform, although you should check your clearance between your fans and/or radiator. 04 and later model Corvette platforms use a water pump that has the pulley only as wide as the belt.

97-03 Corvette/Camaro/Firebird/GTO water pumps have double wide pulley to work with either platform, also have boss for retrofit sensor
2004 and later Corvette/Cadillac platform water pumps

LS SERIES GEN III WATER PUMP SNOUT DIFFERENCES

The snouts are different on car platforms VS truck/SUV platforms due to the mechanically driven fan. The truck/SUV pumps are extended forward, closer to the radiator VS the car platforms, also the pulley is not as wide as they only use 1 style balancer. The truck/SUV balancer also has provision for the mechanical fan, which screw on the snout. The car applications all use electrical fans therefore you will need to install an electrical fan if doing a swap.

LS SERIES GEN III WATER PUMP OUTLET DIFFERENCES

LS1 Corvette/Camaro/Firebird water pump : has no provision for mechanical fan and has water outlet parallel to pulley
Truck water pump : Has provision for mechanical cooling fan and has the outlet perpindicular to the pulley.

Car platforms and truck/SUV platforms have the water outlet in a different location. Since the car platforms have a lower intake, the water outlet is parallel to the drive pulley. On truck platforms, the outlet is perpendicular to the drive pulley. Also, all truck/SUV applications use a closed coolant system with a surge tank, so if you use a truck/SUV water pump, be sure your water levels are above the hose,

LS SERIES GEN III WATER PUMP OUTLET DIFFERENCES

97-03 model water pumps have the thermostat as part of the thermostat housing, and is not removable (at least not by hand). This style uses a large O-ring to seal the housing to the pump. 04-present water pumps have a thermostat that has a separate housing, and the thermostat easily slides out. The O-ring on this model is part of the thermostat. Another visual difference is in the casting. The 97-03 housings have an additional tab on it to hold the wiring in place for the A/C compressor. The 04-present models do not have that tab. The housings are not interchangeable between pumps since the diameter of the thermostat cavity is different and the bolt pattern for the housing is different.

***NOTE : GM water pumps sold after 2005 all have the 2-piece design, meaning if you ordered a new GM water pump for your 1998 Corvette, it came with the newer 2-piece thermostat.

LS SERIES GEN III OIL PANS

All LSx oil pans are interchangeable, pending you swap the corresponding windage (deflector) tray and pickup tubes along with the pan. The windage trays and pickup tubes are specific to the oil pan. All oil feeds are on the LH side of the block, if there's an oil filter on the RH side, the oil pan transfer's the oil to the LH side of the block via piping.

New GTO pan kits from $

Holley LSx Swap Oil Pan

OTHER LSX DIFFERENCES

97-98 Knock sensors have a locking tab on the outside, also a male pin in the middle.  99-05 engines have a round connector.

There were 2 different style knock sensors offered on Gen III LSx engines : A locking tab design, and a standard style connector (same as TPI and LT1 style knock sensor connectors). The locking tab was on all 1997 LS1 engines, and in most (but not all) 1998 LS1 engines. The only way to know what you have is to pull the intake off. You can use either sensor in either block, as long as you have the matching knock harness.

LSx OIL AND COOLANT PLUG LOCATIONS

The LS series engines have alot of strange looking plugs compared to the normal small block chevrolet engine. Below is a small set of photos outlining the plugs and their locations.