Oldsmobile V8 engine

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The 1967 Toronado's 425 V8, the first post war front-wheel drive V8 application.
The 1967 Toronado's 425 V8, the first post war front-wheel drive V8 application.

The Oldsmobile Rocket V8 was the first post-war OHV V8 at General Motors. Production started in 1949, with a new generation introduced in 1964. Like Pontiac, Olds continued building its own V8 engine family for decades, finally adopting the corporate Chevrolet 350 small-block and Cadillac Northstar engine only in the 1990s. All Oldsmobile V-8's were manufactured at plants in Lansing, Michigan.

All Oldsmobile V8s use a 90° bank angle, and most share a common stroke dimension: 3.4375 in (87.3 mm) for early Rockets, 3.6875 in (93.7 mm) for later Generation 1 motors, and 3.385 in (86 mm) for Generation 2. The engine could be classified as a small-block, but Oldsmobile used a higher deck height for a 4.25 in (107.9 mm) stroke to boost displacement to a big-block-like 455 in³ (7.5 L).

The Rocket V8 was the subject of many first and lasts in the automotive industry. It was the first mass-produced OHV V8 in 1949; and was the last carbureted V8 passenger car engine in 1990.

Contents

[edit] Generation 1

The first generation of Oldsmobile V8s ranges from 1949 until 1964. Each engine in this generation is quite similar with the same size block and heads.

[edit] 303

Rocket V8 303 engine
Rocket V8 303 engine

The 303 in³ (5.0 L) engine had hydraulic lifters, an oversquare bore:stroke ratio, a counterweighted forged crankshaft, aluminum pistons, floating wristpins, and a dual-plane intake manifold. The 303 was produced from 1949 until 1953. Bore was 3.75 in (95.2 mm) and stroke was 3.4375 in (87.3 mm). Cadillac used a distantly related motor which appeared in three different sizes through to the 1962 model year; though the Oldsmobile and Cadillac motors were not physically related, many lessons learned by one division were incorporated into the other's design, and the result were two engines known for their excellent power-to-weight ratio, fuel economy, and smooth, strong, reliable running.

The original Oldsmobile V8 was originally to be advertised as "Kettering Power" after chief engineer Charles Kettering, but company policy disallowed the use of his name. So the engine was sold as the Oldsmobile Rocket. The engine was available in Oldsmobile's 88 and Super 88 models, which acquired the nickname Rocket 88.

The 303 was available from 1949 through 1953. 1949 through 1951 "88" 303's came with a 2-barrel carburetor for 135 hp (100 kW) and 253 ft·lbf (343 N·m). 1952 88 and Super 88 V8s used a 4-barrel carburetor for 160 hp (119 kW) and 265 ft·lbf (359 N·m), while 1953 versions upped the compression from 7.5:1 to 8.0:1 for 165 hp (123 kW) and 275 ft·lbf (372 N·m). For comparison, a 1949 Ford Flathead V8 produced just 100 hp (74 kW).

Applications:

[edit] 324

The 324 in³ (5.3 L) version was also produced from 1954 until 1956. Bore was increased to 3.875 in (98.4 mm) and stroke remained the same at 3.4375 in (87.3 mm). All high performance 324s came with 4-barrel carburetors. The 324 was shared with GMC trucks.

The 1954 88 and Super 88 V8s used an 8.25:1 compression ratio for 170 and 185 hp (126 and 137 kW) and 295 and 300 ft·lbf (399 and 406 N·m) respectively.

The 1955 upped the compression to 8.5:1 for 185 hp (137 kW) and 320 ft·lbf (433 N·m) in the 88 and 202 hp (150 kW) and 332 ft·lbf (450 N·m) in the Super 88 and 98. For engines built during the first part of 1955, the 324 skirted pistons had a reputation for failing due to the cast aluminum skirt separating from its steel interior brace. This problem did not appear until the engine had over 50,000 miles (80,000 km) on it. By late 1956, many Olds dealers learned about the problem.

Compression was up again in 1956 for 230 hp (171 kW) and 340 ft·lbf (460 N·m) in the 88 and 240 hp (178 kW) and 350 ft·lbf (474 N·m) in the Super 88 and 98.

Applications:

[edit] 370

A special 370 in³ (6.1 L) variant called the 370 was used in GMC trucks alone, not shared.

[edit] 371

371s were produced from 1957 through 1963. Bore was now 4.0 in (101.6 mm) and stroke was increased to 3.6875 in (93.7 mm) for 371 in³ (6.1 L). 1959 and 1960 371s used green painted valve covers. 4-barrel models used 9.25:1 compression in 1957 and 10:1 in 1958 for 277 hp (206 kW) and 400 ft·lbf (542 N·m) and 305 hp (227 kW) and 410 ft·lbf (555 N·m) respectively. A 1958 2-barrel version was still impressive at 265 hp (197 kW) and 390 ft·lbf (528 N·m), but had problems with early camshaft failures due to the high preload valve spring forces. Then, power nosed downward for the 1959 and 1960 88 model: 270 hp (201 kW) and 390 ft·lbf (528 N·m) for 1959 and 240 hp (178 kW) and 375 ft·lbf (508 N·m) for 1960.

The 371 was also used in GMC trucks.

Applications:

[edit] J-2 Golden Rocket

The 1957 and 1958 J-2 Golden Rocket had three two-barrel carburetors with a vacuum-operated progressive linkage. Only the center carburetor was mechanically connected to the throttle pedal, and it was the only one equipped with a choke. When the center carburetor was opened to 60° or more engine vacuum drawn from the windshield wiper pump would simultaneously open the front and rear carburetors. These carburetors did not open progressively; they were either open or closed. The J-2 engine also had a slightly thinner head gasket, raising compression to 10.0:1. It was advertised with gross power and torque ratings of 312 hp (232 kW) @ 4600 rpm and 415 ft·lbf (562 N·m) @ 2800 rpm. Oldsmobile charged $83 for the J-2 option.

In practice, owners who did not regularly drive hard enough to engage the front and rear carburetors experienced problems with the linkage and carburetor throats becoming clogged, and some J-2-equipped cars had the front and rear carburetors removed and blocked off. The package was expensive to produce, and Oldsmobile discontinued it after 1958.

[edit] 394

Bore was up to 4.125 in (104.8 mm) for the largest first-generation Rocket, the 394 in³ (6.5 L). 394s were produced from 1959 through 1964 and were available on many Olds models. Most 394s used 2-barrel carburetors.

The 394 replaced the 371 in Super 88 and 98 cars for 1959 and 1960 and a detuned version was used in the 88 for 1961 and the Dynamic 88 for 1962 through 1964.

Applications:

[edit] Sky Rocket

The 1961 through 1963 Sky Rocket (and 1964 Rocket) was a 394 in³ (6.5 L) engine. The 10:1 compression 1961 model produced 325 hp (242 kW) and 435 ft·lbf (589 N·m), while the 10.25:1 1962-1964 version upped power to 330 hp (246 kW) and 440 ft·lbf (596 N·m). A special 1963 10.5:1 version was also produced with 345 hp (257 kW).

Applications:

[edit] Starfire

The 1964 Starfire produced 345 hp (257 kW) and 440 ft·lbf (596 N·m) for the 1964 98 Custom-Sports Coupe. It was optional on 1964 98s and Super 88s.

[edit] Aluminum 215 ("Rockette")

From 1961 to 1963 Oldsmobile manufactured its own version of the Buick-designed, all-aluminum 215 engine for the F-85 compact, known as the Rockette. This was a compact, lightweight engine with a dry weight of only 350 lb (159 kg). The Oldsmobile engine was very similar to the Buick engine, but not identical: it had larger combustion chambers with flat-topped (rather than domed) pistons, six bolts rather than five per cylinder head, slightly larger intake valves, and the valves were actuated by independently-mounted rocker arms instead of shaft-mounted rocker arms. With an 8.75:1 compression ratio and a two-barrel carburetor, the Olds 215 had the same rated hp, 155 hp (116 kW) @ 4800 rpm, as the Buick 215, with 220 ft·lbf (300 N·m) of torque at 2400 rpm. With a four-barrel carburetor and 10.25:1 compression, the Olds 215 made 185 hp (138 kW) @ 4800 rpm and 230 ft·lbf (312 N·m) (@ 3200 rpm.

The basic Buick/Olds 215 V8 went on to become the well known Rover V8, remaining in production until the 1990s. The Rover V8 however utilized Buick-style pistons, heads, and valvetrain gear.

The Oldsmobile Rockette engine block formed the basis of the Repco 3 liter engine used by the Brabham team to win the 1966 and 1967 Formula One world championships. The early Repco engines produced up to 300 bhp (220 kW), and featured new SOHC cylinder heads and iron cylinder liners. The 1967 and later versions of the Repco engine had proprietary engine blocks.

[edit] Turbo Jetfire

In 1962 and 1963 Oldsmobile built a turbocharged version of the 215. The small-diameter turbocharger was manufactured by Garrett AiResearch and produced a maximum of 5 lbf/in² (34 kPa) boost at 2200 rpm. The engine had 10.25:1 compression and a single-barrel carburetor. It was rated at 215 hp (160 kW) @ 4600 rpm and 300 ft·lbf (406 N·m) @ 3200 rpm. The high compression ratio created a serious problem with spark knock on hard throttle applications, which led Olds to use a novel water-injection system that sprayed small amounts of distilled water and methyl alcohol (dubbed "Turbo-Rocket Fluid") into the combustion chambers to cool the intake charge. If the fluid reservoir was empty, a complex double-float and valve assembly in the Turbo-Rocket Fluid path would set a second butterfly (positioned between the throttle butterfly and the turbocharger) into the closed position, limiting the amount of boost pressure. Unfortunately, many customers did not keep the reservoir filled, or had mechanical problems with the turbocharger plumbing.

The turbocharger was offered only in a special Jetfire model, which was the first turbocharged passenger car offered for public sale. Only 9,607 were sold in two model years, and many were converted by dealers to conventional four-barrel carbureted form.

[edit] Generation 2

The second generation of Oldsmobile V8s was produced from 1964 through 1990. Most of these engines were very similar, using the same bore centers, although "big-block" versions were produced with a 10.625 in (269.9 mm) deck height rather than 9.33 in (237 mm). Big-block and Diesel versions also used a larger 3.0 in (76.2 mm) instead of 2.5 in (63.5 mm) main bearing journal for increased strength. All generation-2 small-block Olds V8s used a stroke of 3.385 in (86 mm), and all but one big-block used a stroke of 4.25 in (107.9 mm).

These engines, while being a wedge-head, had a unique combustion chamber that resulted from a valve angle of only 6°. This was much flatter than the 23° of the small-block Chevrolet and 20° of the Ford small-block wedge heads. This very open and flat chamber was fuel efficient and had lower than average emissions output. It was the only GM engine to meet US emission standards using a carburetor all the way up to 1990.

[edit] 330

The first second-generation Olds V8 was the 1964 330 in³ (5.4 L). It introduced the standard 3.385 in (86 mm) stroke and used a 3.938 in (100 mm) bore and was produced through 1967. 330s were painted gold and had forged steel crankshafts. While the 4 barrel versions had a harmonic balancer, the 2 barrel versions had only a hub.

[edit] Jetfire Rocket

For 1967, a 330 in³ (5.4 L) Jetfire Rocket was produced.

[edit] 400

The 400 in³ (6.6 L) version was the second tall-deck "big-block" Olds. Two 400 versions were made:

  • 1965 through 1967 Early 400s used a slightly over-square 4.0 in (101.6 mm) bore and 3.98 in (101.1 mm) stroke. This was the desirable 400.
  • 1968 and 1969 400s shared the Olds big-block standard 4.25 in (107.9 mm) stroke with the 455 but used a very undersquare 3.87 in (98.3 mm) bore to comply with GM's displacement restrictions in the A-body cars and reduce tooling costs. This was the less desirable Later 400. Early 400's used the same forged steel crankshaft as the 425's, while the Later 400's used the same cast iron crankshaft of the 455's.

All 400s were painted bronze.

[edit] 4-4-2 Rocket

The 1967 4-4-2 Rocket was a 400 in³ (6.6 L) V8.

[edit] 425

The 425 in³ (7.0 L) big-block was the first tall-deck, "big block" produced from 1965 through 1967. It is arguably the best engine Olds made in the musclecar era, although it never made it into a "musclecar". It used a 4.126 in (104.8 mm) bore and 3.975 in (101 mm) stroke. Most 425s were painted red. All 425 engines had forged steel crankshafts with harmonic balancers.

[edit] Super Rocket

The standard 1965-1967 425 in³ (7.0 L) was called the Super Rocket, and was the most powerful engine option for the Oldsmobile 88 & 98 of 1965 through 1967. Compression ratios of 9 to 1 @ 310 hp (231 kW). or 10.25 to 1 @ 360 hp (268 kW). were available in the U.S.

[edit] Starfire

A special 1965-1967 425 in³ (7.0 L) V8 was the Starfire engine. The main distinguishing features of this engine were a slightly different camshaft profile from the standard ultra high compression engine and factory dual exhaust. This engine was only available in the Oldsmobile Starfire. It shared the same compression ratio of the Toronado Rocket at 10.5 to 1. It also used the .921 in lifter bore size of the Toronado Rocket.

[edit] Toronado Rocket

Another 1967 425 in³ (7.0 L) was the Ultra High Compression Toronado Rocket. Unlike all other 425s, this version was painted slate blue metallic. The Toronado 425 engines had the same .921 in (23.4 mm) diameter lifters of the first-generation Oldsmobile engines rather than the standard .842 in (21.4 mm). This let the engineers increase the ramp speed of the camshaft for more power, 385 hp (287 kW), without sacrificing idle or reliability.

[edit] 455

A larger big-block was introduced for 1968 as the Rocket 455 at 455 in³ (7.5 L) to replace the 425s. It kept the 425's 4.126 in (104.8 mm) bore and bumped the stroke to 4.25 in (107.9 mm). 1968-1969 455s were painted red, except in the Toronado, where they were painted slate blue metallic, while 1970-1976 versions were metallic blue. The "Rocket" name disappeared from the air cleaner identification decal after 1974. Although production of the 455 ended in 1976, a small number were produced through 1978 for power equipment use. Output ranged from 275 to 400 hp (156 to 298 kW).

Applications:

[edit] 350

Produced from 1968 through 1980, the Rocket 350 was entirely different from the other GM divisions' 350's. It used a 4.057 in (103 mm) bore and Oldsmobile small-block standard 3.385 in (86 mm) stroke for 350 in³ (5.7 L). 1968-1974 350s were painted gold, while 1975-1976 models were metallic blue, and the 1977-1980 models were painted GM Corporate Blue. The "Rocket" name disappeared from the air cleaner decal in 1975, the same year that the catalytic converter was added to the emission control systems. Output ranged from 160 to 325 hp (119 to 242 kW). The early Oldsmobile 350s made from 1968 thru 1976 are more desirable engines with heavy castings, beefier crankshafts, and better flowing heads. The later 1977 thru 1980 350 had the "lightweight" castings, including a thinner block with large "windows" in the main bearing bulkheads, crack-prone head castings which were actually manufactured by Pontiac (castings are marked "PMD"; these heads were also used on the 260), and a lightened crankshaft.

The Oldsmobile 350 was produced with an analog electronic port fuel injection system, introduced in the Cadillac Seville of 1976.

Applications:

[edit] L34

Oldsmobile's own L34 350 in³ (5.7 L) V8 was used in the 1979 Hurst/Olds models. The L34 used a 4-barrel carburetor and produced 160 to 170 hp (127 kW) and 275 ft·lbf (373 N·m).

[edit] LF9 Diesel

The LF9 was a 350 in³ (5.7 L) Diesel V8 produced from 1978 to 1985.

Applications;

  • 350N 1978-1985 Chevrolet, Buick, Oldsmobile, Pontiac, and Cadillac cars
    • Early 120 hp (89 kW) 220 ft·lbf (300 N·m) torque
    • Later 105 hp (78 kW) and 205 ft·lbf (278 N·m) torque
  • 350N 1978-1980 GMC and Chevrolet light trucks "pickups"
    • 125 hp (93 kW) and 225 ft·lbf (305 N·m) torque

Variations;

  • 1978-1980 Early block Identified by "D" cast into both sides of block
    • Up to 125 bhp (93 kW)
    • external EGR on some ( Years??)
    • Rumored that some early main and head bolt holes were not tapped to bottom
  • 1981-1985 Improved block Identified by "DX" cast into both sides of block
    • Up to 105 bhp (78 kW)
    • Internal EGR
    • Fully tapped head bolt holes
    • Longer main bolts with fully tapped holes in block
    • Roller Lifters

Diesel Differences;

The Oldsmobile diesel is believed by some to be a converted gasoline engine. While they share the same bore and stroke and some external bolt patterns (transmission and exhaust manifolds) they are quite different.

GM began with a substantially different bottom end when compared with its gasoline cousin.

  • Diesel Blocks
    • 3" diameter injection pump mounts are cast into the top of the lifter valley
    • Camshaft nose modified to incorporate injection pump drive gear
    • Block castings are much thicker and heavier. It's possible to overbore the cylinders by 0.125in without sonic testing.
    • Solid heavy cast main webs were used.
    • Reputedly GM used a higher nickel cast iron alloy for the block and heads.
  • Diesel crankshafts
    • Nodular Iron used in all Diesel cranks
    • Main bearing journals increased to 3.000"
    • Connecting rod journals increased to 2.500"
    • Vibration damper modified to allow eccentric for crank-driven fuel lift pump
  • Diesel Pistons and Rods
    • Diesel rods are shorter at 5.886" long.
    • Diesel pistons have large valve reliefs and steel inserts behind the compression rings and surrounding wrist pin bores.

Fuel Systems;

  • No OEM fuel/water separator was factory installed on any Olds Diesel.
  • Crank eccentric driven fuel lift pump mounted in same location as gasoline fuel pump.
  • Fuel line heater between lift pump and filter.
  • Intake mounted 10 micron fuel filter.
  • Stanadyne Roosamaster DB2 Mechanical Diesel Injection Pump.
  • 1978-79 Pencil Injectors held in by clamp.
  • 1980-85 Poppet injectors screw into head.

Heads;

  • The same 10 head bolt pattern as their smallblock gasoline cousins.
  • The same exhaust manifold bolt pattern as their smallblock gasoline cousins.
  • Have injector pre-chambers and glowplug bosses.
  • Have dual valve springs with rotators.
  • Head variations;
    • D3A Early heads
      • External EGR and Pencil Injectors.
    • D3B Later heads
      • All had Internal EGR
      • Pencil or Poppet Injectors
      • 1 or 2 locating dowels

The Oldsmobile diesel engines gained a reputation for unreliability that is credited with almost permanently damaging the North American passenger diesel market.[citation needed]

[edit] Oldsmobile Intake Manifold Leaking Problems

Most 260, 307, and many 350 Olds engines used aluminum intake manifolds (instead of cast iron) to reduce weight. The light aluminum manifolds were notorious for leaking coolant at the outer corners after the engine had around 75,000 miles (120,700 km) on it[citation needed]. This problem was caused by the differential thermal expansion rates between the aluminum intake manifold and the cast iron block/heads assembly, causing the seal at the intake manifold gasket to fail. On the 350s, many Olds mechanics replaced the aluminum intake with the older cast iron intakes to solve the leak problem[citation needed].

[edit] Oldsmobile Diesel Problems

Head Bolts;

GM used "torque to yield", commonly known as "stretch" or "angle torque", head bolts. This allowed the bolt pattern to remain the same as the gas powered counterpart with an increase in clamping load when compared to standard head bolts. A total of 10 bolts per head were used. Four per cylinder with the center three pairs shared. This permitted the use of the same tooling and reduced setup costs. This design did not provide adequate clamping force under the severe conditions these engines were subjected to. Overheating or excessive cylinder pressure can breach the seal of the head gasket and in severe cases break the bolts.

Pump timing;

The Stanadyne pump was chain driven. With normal use, the chain stretches and the pump delivers fuel too late. The pump timing could be adjusted to return to normal operation.

Water in fuel;

Arguably a major portion of the real problem would have been quite simple to avoid. A water separator was not part of the fuel system on these engines. If you drive a diesel you will pick up water contaminated fuel.

Water will rust the steel internals of the fuel system. Rust will damage the precision parts in diesel fuel injection pumps and high pressure diesel injectors causing erratic operation. Injecting fuel too much prior to TDC on the compression stroke will cause pressure conditions similar to pre-ignition / detonation in gasoline engines. Water in varying amounts will also be injected with the fuel charge. Any rust in the steel fuel lines, fuel filter, pump etc can damage replacement parts and continue to cause injection cycles out of time.

Consumer created fuel problems;

Water in gasoline is dealt with by adding anhydrous alcohol drygas to the fuel. Drygas and diesel don't work and play well together. Naive consumers used drygas in their diesels to combat the water. The alcohol attacked the original governor rings inside the early Stanadyne DB injection pumps and dislodged chunks that blocked the fuel return line flow. These pumps include an ignition advance / retard mechanism based on pump housing fuel pressure. The restriction in the return line caused abnormal ignition timing. A replacement governor ring was introduced by Stanadyne in the mid 1980's to avoid this problem.

The above mix of conditions originating with water in the fuel can combine to create extreme cylinder pressures far exceeding those foreseen by GM engineers damaging the head gasket and sometimes breaking head bolts.

A head gasket leak effectively quenches ignition in the affected cylinder. This allows unburnt fuel and coolant to leak into the crankcase thinning the lubricating oil. It also combines with combustion byproducts to make mild acids that will attack the copper / babbitt bearings and aluminum pistons. A head gasket failure can be particularly damaging in a diesel. A diesel engine has effectively zero piston to head clearance at TDC on the compression stroke. The introduction of coolant into the cylinders can cause hydrolock. Hydrolock typically results in bent / broken crankshafts, pulled threads on main bolts, and bent connecting rods, effectively destroying an engine.

Because the various failures these engines encountered were causally interrelated, and dealership technicians were unfamiliar at best with passenger car diesel engines, recurrent failures were possible because only the most obvious symptoms of trouble were addressed. The "one use only" head bolts were commonly re-used and symptoms in other interrelated systems ignored. Thus, cars could suffer multiple head gasket / head bolt failures from re-use of head bolts or a damaged injection system.

The Oldsmobile Diesel V6 engines, although sharing much of the same production history, were produced on different tooling, where it was feasible to upgrade the head bolt pattern to what is arguably a superior design capable of withstanding more consumer abuse.

[edit] 403

The 455 big-block Olds V8 was replaced in 1977 with the 403 in³ (6.6 L). It used a wide 4.351 in (110.5 mm) bore, the largest ever used in a small-block V8, with the Olds small-block standard deck and 3.385 in (86 mm) stroke. The bore was so wide that it was "siamesed" (similar to the Chevrolet 400 small block motor) — there was no space for coolant flow between the cylinders. This sometimes led to overheating problems. Some very early 403s were painted metallic blue like the 455, but most were painted GM Corporate Blue.

The Olds 403 was used by Buick and Pontiac in addition to Oldsmobile. The engine was only produced through 1979. Output was 185 hp (137 kW) and 320 ft·lbf (433 N·m).

Applications:

[edit] 260

A smaller 260 in³ (4.3 L) V8 was produced in 1975 by decreasing the bore to just 3.5 in (88.9 mm). This was the first powerplant to use the Rochester Dualjet carburetor; all 260s used this small two-barrel carburetor. Production of the 260 V8 ended in 1982 when the 307 became the only gasoline V8 engine in Oldsmobile's line.

The 260 engine was designed for economy and it was the first engine option above the 3.8L Buick V6 engine that had been made standard in many Oldsmobile models by the late 1970s. While the 260 engines were not very powerful compared to the larger 350 and 403 V8 engines, fuel economy was almost as good as the base V6. Compared to the V6, the 260 was also smoother-running, and far more durable.

Most 260s were coupled to the unreliable Turbo Hydramatic 200 transmission as opposed to the THM350 coupled behind the Buick 3.8. A 5-speed manual transmission was also available with some 260-equipped vehicles.

Applications:

[edit] LV8

The LV8 was a 260 in³ (4.3 L) version produced from 1975 to 1982. It produced just 105 hp (78 kW) and 205 ft·lbf (283 N·m).

[edit] LF7 Diesel

The LF7 was a 260 in³ Diesel V8 putting out 90 hp (67 kW) and 160 ft·lbf (220 N·m) torque. It was only used for 1979 as it did not meet 1980 emissions requirements.

Applications;

[edit] 307

A slightly larger 307 in³ (5 L) version was introduced in 1980. It uses the Oldsmobile 3.385 in (86 mm) stroke with a 3.8 in (96.5 mm) bore. All 307s were painted black. It was used in most Oldsmobile models, as well as those from Buick, Cadillac, Chevrolet, and Pontiac. Every 307 was carbureted, and all used 4-barrel carbs. In fact, the 1990 5.0 L Olds V8 was the last carbureted passenger car engine on the market in the United States (excluding the 1991 Ford LTD Crown Victoria Police Interceptor 351 in³ and the 1993 Mazda pick up truck, the very last carbureted road use vehicle sold in the US).

Applications:

[edit] LV2

Oldsmobile used the popular LV2, a 307 in³ (5.0 L) engine, commonly known by the VIN code "Y", from 1980 to 1990. It was used by every domestic GM automobile marque. Roller lifters, floating piston wrist pins, and swirl port intake runners were added in 1985.

The 307 "Y" produced 148hp and 250lb-ft in 1980-1984 models and 140hp and 255lb-ft in 1985-1990 models. All LV2s feature a 4-barrel carburetor.

Y-version applications:

[edit] LG8

The LG8 was a modern 307 in³ 5.0 L High-Output derivative of the LV2 produced from 1983 to 1987. Performance modifications included a "hot" camshaft (in reality, the base model 455 camshaft), stiffer valve springs, heavy-duty exhaust valves, the larger vibration damper from the 350, a Y-pipe dual-outlet exhaust system, and richer secondary metering rods in the carburetor. It was offered in the Hurst/Olds version of the Oldsmobile Cutlass Calais and in the 442 version of the Oldsmobile Cutlass Salon. Output for 1983-1985 was 180 hp (134 kW) and 245 ft·lbf (318 N·m). Revisions to the engine for 1986 included roller lifters with a slightly smaller camshaft, new heads with smaller, swirl-port intake runners, floating piston pins, and larger piston dishes for lower compression. These changes increased torque to 250 ft·lbf (325 N·m) but lowered power to 170hp, while lowering the RPM at which peak horsepower and torque was achieved.

Applications:

[edit] Generation 3

The Oldsmobile V8 ended production in 1990. The company later introduced a new vehicle, the Oldsmobile Aurora, with a new generation of V8 power. Based on the Cadillac Northstar engine, the Oldsmobile Aurora engine was a DOHC design.

[edit] See also

From the 1950s through the 1970, each GM division had its own V8 engine family. Many were shared among other divisions, but each design was unique:

GM later standardized on the later generations of the Chevrolet design:

[edit] External links