RPO codes
GENERATION III
LS1 - 5.7 (346 CI) - Between 305-350 hp and 335-375 ft·lb
1997-2004 Chevrolet Corvette C5, excluding Z06
1998-2002 Chevrolet Camaro Z28, SS
1998-2002 Pontiac Firebird Formula, Trans Am, Trans Am WS6
2004 Pontiac GTO
*97-98 Had Perimeter Bolt Valve Covers
LS6 - 5.7 (346 CI) - 385(01 Vette only)/405 hp and 385(01 only)/400 ft-lbs.
2001-2004 Chevrolet Corvette C5 Z06
2004-2005 Cadillac CTS V-Series
*Basically the same as an LS1 but with better heads (243 head castings) a more aggressive cam, and LS6 intake manifold make up the power differences.
TRUCK ENGINES - STILL GENERATION III
The truck engines are very much like the LS1/LS6 and are still classified as a Gen III engine. They are mainly iron with the exception of the LM4/L33, and as a result weigh approximately 80+ lbs. more. All the parts from the LS series can bolt on to these engines and is recommended for any swap as the accessories and intake manifold usually fit better from an F-body. The 4.8 and 5.3 can both be punched out to a 5.7 (346 Cubic Inches) simply with a bigger bore (the 5.3) or a bigger bore and the 5.3 crank (in the 4.8's case).
4.8 - LR4
5.3 - LM4, LM7, L33, L59
6.0 - LQ4, LQ9
LR4 - 270-295 hp and 285-305 ft·lb
*Iron Block
2003-present Chevrolet Express 2500-3500/GMC Savana 2500-3500
1999-2007 Chevrolet Silverado/GMC Sierra
1999-2006 Chevrolet Tahoe/GMC Yukon
LM7 - 285-295 hp 325-335 ft·lb
*Most common 3rd gen LSx engine - Iron Block
2002-2005 Cadillac Escalade 2WD
2002-2006 Chevrolet Avalanche
2003-2007 Chevrolet Express/GMC Savana
1999-2007 Chevrolet Silverado 1500
1999-2007 GMC Sierra 1500
1999-2006 Chevrolet Suburban/GMC Yukon XL
1999-2006 Chevrolet Tahoe/GMC Yukon
LM4 - Identical to the LM7 in power/torque
*Aluminum Block, limited production
2004 Chevrolet TrailBlazer EXT
2004 GMC Envoy XL
2004 Chevrolet SSR
L33 - 310 hp - High Output version of the LM7
*Aluminum Block
2005-2007 Chevrolet Silverado 1500 4WD
2005-2007 GMC Sierra 1500 4WD
L59 - Flex Fuel version of the LM7 (power/torque same)
2002-2007 Chevrolet Silverado 1500
2002-2006 Chevrolet Tahoe/GMC Yukon
2002-2006 Chevrolet Suburban/GMC Yukon XL
2002-2007 GMC Sierra 1500
LQ4 - 6.0L (364 CI) - 300-325 hp / 360-370 ft·lb
*Iron Block
Chevrolet Express/GMC Savana
Chevrolet Silverado 2500 Pickup, 3500 Pickup, Crew Cab, and Chassis Cab/GMC Sierra 2500 HD Pickup and Crew Cab, C3, Denali, and 3500 Pickup and Chassis Cab, 1500HD Crew Cab
Chevrolet Suburban/GMC Yukon XL Denali
Hummer H2 SUT
GMC Yukon Denali
LQ9 - 6.0L (364 CI) - 345hp / 380 ft·lb
*Iron Block
2002-2006 Cadillac Escalade
2002-2006 Cadillac Escalade EXT
2003-2006 Cadillac Escalade ESV
2003-2007 Chevrolet Silverado SS
2004-2005 Chevrolet Silverado and GMC Sierra Vortec HO Edition Only 2006-2007 Chevrolet Silverado and GMC Sierra VortecMAX Option
GENERATION IV - Generation IV engines are very similar to Gen III and most parts can be interchanged. The Gen IV was produced with displacement on demand and variable valve timing in mind. Not all have these features, but they are available. Also they have a 58x crank trigger, front cam sensor, and side mounted Knock sensors.
L76 - 360hp /385 ft-lbs. 6.0L (364 Cubic Inches)
2008 Pontiac G8
L98 - 362hp /391 ft-lbs. 6.0L (364 Cubic Inches)
2007-2008 Chevrolet Lumina SS
2007-2008 Chevrolet Caprice SS
L99 - 400hp /395 ft-lbs. 6.0L (364 Cubic Inches)
*Derived from the LS3 and with Displacement on Demand
2010 Chevrolet Camaro
LS2 - 6.0L (364 CI) - 400 hp/400 ft.-lbs.
2006-2007 Cadillac CTS-V
2005-2007 Chevrolet Corvette
2005-2006 Chevrolet SSR
2006-2008 Chevrolet TrailBlazer SS
2004-2007 Holden Special Vehicles (all V8 models)
2005-2006 Pontiac GTO
2008-2010? Saab 9-7X Aero
2005-2006 Vauxhall Monaro VXR
LS3 - 6.2L (376 CI) - 430 hp / 424 ft.-lbs.
April 2008-present Holden Special Vehicles (all V8 models)
2008-present Chevrolet Corvette
2009 Pontiac G8 GXP
2010 Chevrolet Camaro
LS4 - 5.3L (325 CI) - 303 hp / 323 ft.-lbs.
2006-2008 Chevrolet Impala SS
2006-2007 Chevrolet Monte Carlo SS
2005-2008 Pontiac Grand Prix GXP
2008 Buick LaCrosse Super
*Aluminum FWD Block w/ LS6 Heads
LS7 - 7.0L (427 CI) - 505 hp / 470 ft.-lbs.
2006-2008 Chevrolet Corvette Z06
2008 HSV W427
LS9 - 6.2L (376 CI) Supercharged - 638 hp / 604 ft.-lbs.
*Based on the LS3
2009 Chevrolet Corvette ZR1
TRUCK ENGINES - GENERATION IV
LY2- 4.8 2007-present Silverado/Sierra, Express/Savana , Tahoe/Yukon
LMG- 5.3 (Iron block/AFM/FF) 2007-present Silverado
LH6- 5.3 (Alum block/AFM) 2005-present TB/Envoy, 2007-present Silverado
LC9- 5.3 (Iron block/AFM/FF) 2007-present Silverado
LY5- 5.3 (Alum block/AFM/FF) 2007-present Silverado
LH8- 5.3 (Alum block) H3 Alpha, Colorado/Canyon
LY6 - 6.0 (364 CI) - Same as LQ4, but Gen IV.
*Variable Valve Timing
2007-present Chevrolet Silverado HD
2007-present GMC Sierra HD
2007-present Chevrolet Suburban 3/4 ton
2007-present GMC Yukon XL 3/4 ton
L76 - 6.0 (364 CI) - 367hp / 375 ft.-lbs.
*Basically the Gen IV replacement for the LQ9
*Variable Cam Phasing & Active Fuel Management
2007-present Chevrolet Suburban
2007-present Chevrolet Avalanche
2007-present Chevrolet Silverado
2007-present GMC Sierra
2007-present GMC Yukon XL
LFA - 6.0 (364 CI) - 332 hp / 367 ft.-lbs.
*Active Fuel Management
*Late-intake valve timing system
*Higher 10.8:1 compression ratio
2008-present Chevrolet Tahoe Hybrid
2008-present GMC Yukon Hybrid
2009-present Cadillac Escalade Hybrid
2009-present Chevrolet Silverado Hybrid
2009-present GMC Sierra Hybrid
L92 - 6.2L (376 CI) - 380/403 hp and 403/415 ft.-lbs.
2007-08 Cadillac Escalade
2008 Chevrolet Tahoe
2007-08 GMC Sierra Denali
2008 Hummer H2
2007-09 GMC Yukon Denali/Denali XL
L9H- 6.2L (376 CI)
2009 Cadillac Escalade
2009 GMC Sierra Denali
2009 Hummer H2
2009 GMC Yukon Denali/Denali XL
2009 Silverado LTZ, Tahoe LTZ
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Quick summary of the major engines and their compression ratios and GM part #s:
LS1...346c.i. 5.7L 10.19:1 25534322
LS6...346c.i. 5.7L 10.46:1 12578104/12562190
LR4...293c.i. 4.8L 9.47:1
LM4...325c.i 5.3L 9.49:1
LM7...325c.i 5.3L 9.49:1 12562201
L59...325c.i. 5.3L 9.49:1
LQ4...364c.i. 6.0L 9.41:1 12575147/12575148
LQ9...364c.i. 6.0L 10.08:1 12499467