The LA engine is a family of overhead-valve small-block 90° V-configured gasoline engines built by Chrysler Corporation between 1964 and 2003. Primarily V8s, the line includes a single V6 and V10, both derivations of its Magnum series introduced in 1992. A replacement of the Chrysler A engine, they were factory-installed in passenger vehicles, trucks and vans, commercial vehicles, marine and industrial applications. Their combustion chambers are wedge-shaped, rather than polyspheric, as in the A engine, or hemispheric in the Chrysler Hemi. LA engines have the same bore spacing as the A engines.
LA engines were made at Chrysler's Mound Road Engine plant in Detroit, Michigan, as well as plants in Canada and Mexico. The "LA" stands for "Light A," as the 1956–1967 "A" engine it was closely based on and shares many parts with was nearly 50 pounds heavier. The "LA" and "A" production overlapped from 1964–1966 in the U.S. and through 1967 in export vehicles when the "A" 318 engine was phased out.
The basic design of the LA engine would go unchanged through the development of the "Magnum" upgrade (1992–1993), and continue into the 2000s with changes to enhance power and efficiency. The LA engine was available until 1991, when it was superseded by the Magnum version. It used hydraulic lifters and a two-barrel carburetor for most of its production, though four-barrel Carter Thermo-Quad and Rochester Quadrajet carburetors were used in police applications starting in 1978 and 1985, respectively. The 318 two-barrel ELD received roller lifters and a fast-burn chambered cylinder head in 1985 (the four-barrel police ELE 318 continued to use modified J heads and hydraulic flat valve lifters through 1989).
Throttle-body electronic fuel injection was factory equipment on the 1981–1983 Imperial. From 1988 to 1991, another throttle-body fuel injection system was used for truck and van applications.
- 1983–1989 Chrysler Fifth Avenue
- 1981–1983 Imperial
- 1968–1981 Chrysler Valiant
- 1977–1981 Chrysler LeBaron
- 1979–1982 Chrysler New Yorker
- 1981–1983 Imperial
- 1975–1983 Chrysler Cordoba
- 1976–1980 Dodge Aspen
- Dodge Charger
- Dodge Challenger
- Dodge Coronet
- 1968–1976 Dodge Dart
- 1977–1989 Dodge Diplomat
- 1991–1992 Dodge Dakota
- 1971–1972 Dodge Demon
- 1973–1976 Dodge Dart Sport
- 1970–1980 (Valiant) Dodge Super Bee (Mexico)
- 1971–1979 Dodge GTX (Argentina)
- 1978–1979 Dodge Magnum
- 1980–1983 Dodge Mirada
- 1967–1992 Dodge Ram
- Dodge Ram Van
- 1974-1992 Dodge Ramcharger
- 1968–1974 Plymouth Barracuda
- Plymouth Belvedere
- 1970–1976 Plymouth Duster
- 1967–1972 Plymouth Fury
- 1972–1989 Plymouth Gran Fury
- 1964–1974 Plymouth Satellite
- 1974–1981 Plymouth Trail Duster
- 1968–1976 Plymouth Valiant
- 1976–1980 Plymouth Volaré
- 1981–19?? Allard J2X2
- 1976-1979 Monteverdi Safari
- 1977–1980 Monteverdi Sierra
- Volkswagen 11-160/22-160 (Ethanol-powered VW truck)
- Dodge E-13 (Ethanol-powered truck)
- Companhia Brasileira de Tratores (CBT) 3000 and 3500 (Ethanol-powered tractor)
340 V8<span class="anchor" id="340"></span>
thumb|The base came with a 4-barrel carburetor and produced gross
In the mid-1960s, Chrysler decided to adapt the small block V8 into a lightweight, high output engine equally suited for drag strip or street performance use. Its block was bored out to but its stroke left unchanged, resulting in the engine introduced for the 1968 model year. Anticipating higher loads resulting from racing operation, the engineers fitted a forged shot peened steel crankshaft instead of the cast steel unit used in the 318. This also included shot peened hammer-forged steel connecting rods and high compression cast aluminum pistons with full floating pins. A 4-barrel carburetor was mated to a high-rise, dual plane intake manifold feeding high-flow cylinder heads Its big ports used intake and exhaust valves. An aggressive cam was fitted to take advantage of the much better breathing top end. The 1968 4-speed cars got an even hotter cam, but it was discontinued for 1969, where both automatic and manual cars shared the same cam. The engine was equipped with hydraulic lifters and two bolt main bearing caps, leading some to initially underestimate the 340's potential. The 1968–71 340's compression ratio was 10.5:1, placing it near the limit of what was possible on pump gasoline during that era. The 340 also used additional heavy-duty parts, such as a double-row roller timing chain and sump-mounted windage tray. Power output was officially stated as gross for the 4 barrel.
In 1970, Chrysler introduced a special triple carburetor version of the 340 with triple 2-barrels at gross. Exclusively called the catchy Six-Pack on the Trans-Am targeted Dodge Challenger TA models, the same configuration was used by Plymouth for its Trans-Am AAR 'Cuda, called just the "340-6" or "six barrel". This race-oriented version of the already high-performance 340 featured an aluminum intake manifold mounting three Holley carburetors, a dual points ignition system, and a heavy duty short block with additional webbing to allow for aftermarket installed 4 bolt main bearing caps. The application-specific cylinder heads featured relocated intake pushrod passages with offset rocker arms that allowed the pushrods to be moved away from the intake ports, which could improve airflow if the pushrod-clearance "hump" was ground away from the intake port by the end user.
The combination of increasingly stringent emission controls, lowered octane, rising gasoline prices, and insurance company crackdown on high-performance vehicles saw the relatively expensive 340 detuned in 1972 with the introduction of low compression (8.5:1) small valve heads, and by mid-year a cast nodular iron crankshaft and a variety of other emissions related changes. For the 1974 model year, it was replaced by the engine.
- Chrysler Valiant Charger (Australia)
- Dodge Challenger
- Dodge Charger
- Dodge Dart
- 1971–1972 Dodge Demon
- Dodge Super Bee
- Plymouth Barracuda
- Plymouth Duster
- Plymouth Road Runner
- Plymouth Sport Fury GT
- Monica 560
360 V8<span class="anchor" id="360"></span>
thumb| V8 in a Li'l Red Express Truck
The LA has a bore and stroke of . It was released in 1971 with a two-barrel carburetor. The 360 used the large intake port 340 heads with a smaller intake valve of . In 1974, with the introduction of the code E58 4-barrel dual-exhaust version, at SAE net, it became the most powerful LA engine with the end of 340 production. Power started dropping from 1975 on as more emission controls were added resulting with the 1980 E58 engine only producing SAE net. Starting with 1981, the 360 was exclusively used in Dodge trucks and vans.
The 1978–1979 Li'l Red Express truck used a special high-performance 360 4-barrel engine with factory production code EH1 that was rated at 225 SAE Net HP in production form The EH1 was a modified version of the E58 360 police engine (E58) producing net at 3800 rpm due in part, that as it was installed in a "truck", and not a car, it did not have to use catalytic converters (1978 only) which allowed for a free-flowing exhaust system. Some prototypes for the EH1 featured Mopar Performance W2 heads, although the production units had the standard 360 heads. Some police package cars came from the factory with a steel crank and h-beam rods. There was also a "lean burn" version of the 360. The LA360 was replaced in 1993 by the 5.9 Magnum, which shared some design parameters with the LA360, but the majority of its components were different.
Due to additional modifications, the prototype Li'l Red Express truck tested by various period magazines ran appreciably stronger than actual production examples.
- Chrysler 300
- Chrysler Valiant & Valiant Charger (Australia)
- Chrysler by Chrysler (Australia)
- 1975–1979 Chrysler Cordoba
- 1978–1979 Chrysler LeBaron
- 1977–1980 Chrysler New Yorker
- 1971–1980 Chrysler Newport
- 1976–1980 Dodge Aspen
- 1974 Dodge Challenger
- 1974–1978 Dodge Charger
- 1974–1976 Dodge Coronet
- 1974–1976 Dodge Dart
- 1978–1979 Dodge Diplomat
- 1978–1979 Dodge Magnum
- 1971–1978 Dodge Monaco
- 1971–1973 Dodge Polara
- 1971–1980 Dodge D Series
- 1981–1992 Dodge Ram
- 1979–1992 Dodge Ram Van/Dodge Ram Wagon
- 1971–1992 Dodge Sportsman/Dodge Tradesman
- 1974–1992 Dodge Ramcharger
- 1974–1981 Plymouth Trail Duster
- 1974–1975 Plymouth Road Runner
- 1974 Plymouth Barracuda
- 1974–1976 Plymouth Duster
- 1971–1978 Plymouth Fury
- 1975–1977, 1980 Plymouth Gran Fury
- 1976–1980 Plymouth Volaré
- 1974–1983 Plymouth Voyager
- 1979–1980 Dodge St. Regis
- 1978–1979 Dodge Li'l Red Express
- (in Bristol-modified form)
- Bristol 603
- Bristol 412
- (in Bristol-modified form with turbocharger)
- Bristol Beaufighter
- Bristol Brigand
- Bristol Beaufort
Throttle-body injected LA engines<span class="anchor" id="TBI"></span>
The last variation of the LA series to be introduced before the Magnum upgrade was the 1988–92 throttle-body fuel injected, roller cam engine. The first engines to receive these modifications were the V8 and V6 engines. A Holley/Chrysler-designed, single-point, twin-injector throttle body assembly was mounted atop a slightly redesigned cast iron intake manifold. An in-tank electric pump and reservoir replaced the earlier mechanical (camshaft-eccentric driven) pump. The valvetrain was upgraded to include hydraulic roller lifters; however, cam specifications remained essentially unchanged. The resulting engine was somewhat improved as to power and efficiency. The 5.9 L V8 engines followed suit in 1989, but also received the overall improved "308" cylinder heads (casting number 4448308) that featured significantly higher flowing exhaust ports and a return to the original 1971 (non-fast burn) combustion chamber. However, with other manufacturers already introducing the superior multi-point fuel injection system, Chrysler considered a more drastic upgrade program. Cylinders were numbered from the front of the engine to the rear; cylinders 1, 3, 5, and 7 were found on the left (driver side) bank, or "bank 1," with the even numbers on the other bank.
Coolant passages were located between the cylinders. The gerotor-type oil pump was located at the bottom-rear of the engine, and provided oil to both the crankshaft main bearings and the cylinder heads (via the lifters and pushrods, as opposed to a bored passage on LA engines).
Chrysler's engineers also redesigned the oil seals on the crankshaft to improve anti-leak seal performance. The oil pan was also made from thicker steel, and was installed with a more leak-resistant silicone-rubber gasket.
Gasoline was supplied to the intake manifold through a pair of steel rails that fed eight Bosch-type, top-fed, electronically actuated fuel injectors; there was one injector located in each intake runner. Each cylinder had its own injector, thus making the fuel system a "multi-point" type. Fuel pressure was regulated by a vacuum-controlled pressure regulator, located on the return side of the second fuel rail. Excess fuel was thereafter delivered back to the fuel tank. (Later versions had the regulator and filter mounted at the in-tank pump.) These heads were cast iron units with new wedge-shaped combustion chambers and high-swirl valve shrouding. A PCV, or Positive Crankcase Ventilation system, introduced oil vapor and unburnt fuel vapors from the crankcase to the intake, allowing the engine to re-use these as well. As such, a new engine control computer was developed for vehicles powered by Magnum engines, known as the JTEC. The new Powertrain Control Module was more complex and more intelligent, and added programming meant it could also control automatic transmission and other powertrain functions; its firmware could also be reprogrammed ("reflashed") via the same OBD-II port. With the introduction of the JTEC, the EGR system was dropped from Magnum engines.
Applications:
- 1992–2003 Dodge Dakota
- 1992–2003 Dodge Ram Van/Dodge Ram Wagon
- 1992–2001 Dodge Ram
Magnum 5.2 L V8 <span class="anchor" id="5.2"></span>
thumb|A 5.2L Magnum V8 as installed in a 1994 [[Jeep Grand Cherokee]]
The 5.2 L Magnum, released in 1992, was an evolutionary development of the LA engine with the same displacement. The 5.2 L was the first of the Magnum upgraded engines, followed in 1993 by the 5.9 L V8 and the 3.9 L V6.
At the time of its introduction, the 5.2 L Magnum created at 4,100 rpm and at 3,000 rpm. It was upgraded in 1998 to at 4,000 rpm and at 3,250 rpm. The 5.9 L came factory-installed in 1998–2001 Dodge Dakota R/T pickups and 2000–2003 Dodge Durango R/T SUVs. It was also installed in the Jeep Grand Cherokee Limited 5.9, only available in 1998. The 5.9 L Magnum was available until the 2003 model year, when it was replaced with the 5.7 L Hemi V8 engine.
Although the pre-Magnum (1971–92) and Magnum versions of the are both externally balanced, the two are balanced differently (the Magnum version uses lighter pistons) and each requires a uniquely balanced damper, flywheel, drive plate, or torque converter. Bore and stroke size was ; compression ratio was 9.1:1. this engine's roots trace to the genesis of the 5.2 L Magnum V8 in 1988.
The Magnum V10 has a cast iron block, and was rated for (1994–1998) and (1999–2003) at 4,100 rpm and at 2,400 rpm.