GM Regular Production Options (RPO) Codes codes are frequently used to describe a particular engine combination in a particular vehicle. Some RPO's used the same number in different years but motors might have slightly different equipment.
L-19 | 1988-1990, Mark IV 454/230HP, light duty trucks, 4-bolt Mark
IV block, cast crank, cast pistons, hydraulic cam, open chamber oval port
heads, compression 8.25:1 1991-1995, Gen V 454/230HP, light duty Trucks, 4-bolt block, cast crank, cast pistons, hydraulic cam, Gen V oval ports open chamber heads, compression: 8.25:1 |
L-34 | 1966-1969, 396/350,360HP, 2-bolt ('66: 4) block, steel crank,
cast pistons, closed chamber oval ports heads , High lift hydraulic cam,
compression 10.25:1, Holley carb ('66-'68), Quadrajet carb ('69-'69),
cast hi-rise intake 1970, 402/350HP, same as above but bigger bore and Quadrajet carb, 2-bolt block |
L-35 | 1965-1967, 396/325HP, 2-bolt block, steel crank, cast pistons,
closed chamber oval port heads, hydraulic cam, compression: 10.25:1, Holley
4 barrel carb, cast hi-rise intake 1968-1969, 396/325HP, 2-bolt block, cast crank, cast pistons, closed chamber oval port heads, hydraulic cam, compression: 10.25:1, Quadrajet carb, cast intake |
L-36 | 1966-1969, 427/385HP or 390HP, 2-bolt block, steel crank, cast
pistons, closed chamber oval port heads, High-lift hydraulic cam, compression:
10.25:1, Holley or Quadrajet carb, cast intake, aluminum Low-rise Quadrajet
intake on 1968-1969 Corvettes |
L-66 |
1969, 396/265HP, 2-bolt block, steel crank, cast pistons, closed chamber oval port heads, hydraulic cam, compression: 9.0:1, 2 barrel
carb, cast intake
|
L-68 | 1967-1969, 427/400HP Corvettes, same as L-36 but with three
2 barrel carb, cast intake |
L-71 | 1967-1969, 427/425HP or 435HP Corvettes, same as L-72 but three
2 barrel Holley carb, aluminum rectangular port intake |
L-72 | 1966-1968, 427/425HP, 4-bolt block, steel "Tuftride" crank,
forged pistons, closed chamber rectangular port cast heads, mechanical cam,
compression: 11.1:1, Holley 800cfm carb on aluminum hi-rise intake |
L-78 | 1965-1969, 396/375HP, 4-bolt block, steel "Tuftride" crank,
forged pistons, closed chamber heads with rectangular ports, mechanical
cam, compression: 11.0:1, Holley 800cfm carb, aluminum hi-rise intake 1965, 396/375HP, Z-16 Chevelle, same as above, but with high-lift hydraulic cam, 780cfm Holley carb 1965, 396/425HP, Corvette and Passenger Cars, same as 396/375HP L-78 with mechanical cam 1970, 402/375HP, same as 1965-1969 396/375HP, but bigger bore, mechanical cam |
L-88 | 1967-1969 427/430HP Corvette, 4-bolt block, steel "Tuftride"
crank, 7/16" "dot" rods, forged "floating pin" pistons, 1/16" pistonrings,
mechanical crank, closed chamber rectangular ports aluminum heads (1967-1968),
open chamber rectangular ports aluminum heads (1969), 7/16" pushrods, compression:
12.5:1, Holley 850cfm carb on aluminum hi-rise intake |
L-89 | 1968-1969 396/375HP, same as L-78, but with optional closed
chamber rectangular port aluminum heads for Nova and Camaro 1968-1969 427/425HP Corvette, same as L-71, but with optional closed chamber rectangular port aluminum heads |
LS-1 |
1969 427/335HP Passenger Car, 2-bolt block, cast crank, cast pistons, closed chamber
oval port heads, hydraulic cam, compression: 10.25:1, Quadrajet carb,
hi-rise cast intake
|
LS-3 |
1970 402/330HP, 2-bolt block, cast crank, cast pistons, closed chamber oval port heads,
hydraulic cam, compression: 10.25:1, Quadrajet carb, Lo-rise cast intake
1971 402/300HP, same as above, but with open chamber oval port heads, compression: 8.5:1 1972 402/240HP, with dual exhaust or 402/210HP with single exhaust, otherwise the same as 1971 LS-3 |
LS-4 |
1970 454/345HP, 2-bolt block, steel crank, cast pistons, hydraulic cam, closed
chamber oval port heads, compression: 10.25:1, Quadrajet carb on cast intake
1973-1974 454/215HP, 235HP, 245HP, 270HP, same as above, but 2-bolt block, cast crank, open chamber oval port heads, compression: 9.0:1 |
LS-5 |
1970 454/360HP or 390HP, 2 or 4-bolt block, steel
crank, cast pistons, hydraulic
cam, closed
chamber oval port
heads,
compression: 10.25:1,
Quadrajet carb on
Low-rise cast intake
1971 454/365HP, same as above, but with open chamber oval port heads, compression: 8.5:1 1972 454/240HP with single exhaust or 270HP with dual exhaust, otherwise it is the same as 1971 LS-5 454 |
LS-6 | 1970 454/450HP Chevelle, 4-bolt block, steel "Tuftride" crank,
7/16" "dot" rods, forged "floating Pin" pistons, closed chamber rectangular
port heads, compression: 11.0:1, mechanical cam, Holley 800cfm carb on aluminum
Low-rise intake 1971 454/425HP Corvette, same as above, but with open chamber rectangular port aluminum heads, Monte Carlo and Chevelle have cast open chamber rectangular port heads, compression: 9.0:1 |
LS-7 | 454/465HP never factory installed in a vehicle, it became available
in 1970 as an "over the counter" crate motor or could be built with "over
the counter" parts, 4-bolt block, steel "Tuftride" crank, 7/16" "dot" rods,
forged "floating pin" pistons, 1/16" pistonrings, mechanical cam, aluminum
open chamber rectangular port heads, compression: 12.5:1, 3/8" pushrods,
Holley 850cfm carb on aluminum hi-rise intake, original intended for Corvette
|
ZL-1 | 1969 427/430HP, Camaro and Corvette, same as L-88 except ZL-1
used an aluminum block, only installed in 2 Corvettes and 69 Camaros, some
engines sod "over the counter" |
vette.ch: home last modified: Di. 26.11.2002 0:49