Oldsmobile V8 engine 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 journal for increased strength. All generation-2 small-block Olds V8s use a stroke of 3.385 in (86 mm), and all but one big-block use 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.



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.



Jetfire Rocket

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



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.



4-4-2 Rocket

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



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.



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 or 10.25 to 1 were available in the U.S.



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.



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.



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, 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:

* Oldsmobile Cutlass
* Oldsmobile Vista Cruiser
* Oldsmobile 442
* Oldsmobile Delta 88
* Oldsmobile 98
* 1968-1970 Oldsmobile Toronado, 375 hp
* 1968-1970 Oldsmobile Toronado GT (W34), 400 hp



350

Produced from 1968 through 1980, the Rocket 350 was entirely different from the other GM divsions 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 1975-1980 models were metallic blue, at which time the "Rocket" name disappeared from the air cleaner decal. Output ranged from 160 to 320 hp (119 to 238 kW). All Oldsmobile 350 engines had cast-iron crankshafts with harmonic balancers.

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

Applications:

* Cadillac Seville
* Oldsmobile Cutlass
* Oldsmobile Vista Cruiser
* Oldsmobile 442
* Oldsmobile Delta 88
* Oldsmobile 98
* Oldsmobile Toronado
* Oldsmobile Omega



L34

Oldsmobile's own L34 350 in³ (5.7 L) V8 was used in the 1976-1980 Hurst/Olds models. The L34 used a 4-barrel carburetor.



LF9

The LF9 was a Diesel version of the 350 in³ (5.7 L) V8. It was produced from 1978 to 1985 and was used by most domestic GM marques. 1980-1985 versions used roller lifters. These engines were notably unreliable, a situation detailed below, and at the Oldsmobile Diesel V6 engine page.



Oldsmobile Diesel problems

Despite the fact that these engines looked in large part like their gasoline cousins, they were indeed quite different. The castings were much thicker and heavier, and a higher quality alloy was used for the block and heads. The main bearing journals were also increased to 3.000 inches in size to compensate for the higher operating stresses and pressures that diesels exert on their reciprocating parts. The primary problem with GM's Diesel engines of the 1970s was due in large part to poor fuel quality (diesel fuel was notoriously filthy and contaminated with water in the late 1970's), which caused corrosion in the fuel injection pump. This corrosion could (and often did) cause an incorrect injection cycle, which would produce abnormally high cylinder pressures. This in turn would cause the cylinder head to "lift" up off of the block, and stretch (or even break) the head bolts. Once the head gasket was compromised, the gasket would leak coolant into the cylinder. At 22.5:1 compression, there was little volume left in the cylinder at TDC. The uncompressible quality of liquids means that the engine would hydro lock, breaking pistons, crankshafts, connecting rods, and other parts, resulting in complete and catastrophic engine damage. Why then, did other Diesel engines, from GM and other companies, not have these problems? The answer lies in the lack of an effective water separating system, such as can be found on other diesel applications. Overall, the main ingredients of disaster that affected this engine lie in: 1) A poorly designed fuel system, which was fostered by a desire to insulate the consumer from the unpleasant aspects of Diesel ownership. 2) A misguided attempt to market the diesel engine as if it was as convenient to operate and maintain as a gasoline engine. 3) A poorly trained service staff which often used the incorrect oils and service procedures for this (and any, for that matter) Diesel engine. These factors combined to create the ultimate downfall of this engine. In the hands of an experienced diesel operator, these engines can (and often do) travel for hundreds of thousands of trouble free miles. However, for owners who would just "gas and go", this engine was particularly ill suited to the task.



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. Like the 455, it was painted metallic 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:

* 1977-79 Buick Riviera
* 1977-79 Buick Electra/Park Avenue
* 1977-79 Buick Estate Wagon
* 1977 Oldsmobile Cutlass
* 1977 Oldsmobile Vista Cruiser
* 1977 Pontiac Bonneville
* 1977-1978 Oldsmobile Delta 88
* 1977-1978 Oldsmobile Toronado
* 1977-1979 Oldsmobile 98
* 1977-1979 Oldsmobile Custom Cruiser
* 1977-1979 Pontiac Trans Am
* 1977 Grand Prix available with California Emissions Only
* 1977-1979 GMC Motor Homes



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 3.8 V6 Buick engine that had been made standard in many Oldmobile models by the late 1970's. 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:

* 1975-77 Pontiac Ventura, Oldsmobile Omega, and Buick Skylark
* 1975-82 Oldsmobile Cutlass
* 1978-82 Buick Regal



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).



LF7

The LF7 was a Diesel version of the 260 in³ (4.3 L) V8 produced in 1979 and 1980. Output was just 90 hp (67 kW) and 170 ft·lbf (230 N·m). These engines were notably unreliable, a situation detailed at the Oldsmobile Diesel V6 engine page.



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 1994 Mazda pick up truck, the very last carbureted road use vehicle sold in the US).

Applications:

* 1980-1985 Oldsmobile Delta 88
* 1980-1984 Oldsmobile 98
* 1980-1985 Oldsmobile Toronado
* 1980-1990 Oldsmobile Custom Cruiser
* 1980-1985 Buick Lesabre
* 1980-1984 Buick Electra
* 1980-1985 Buick Riviera
* 1980-1990 Buick Estate Wagon
* 1986-1990 Cadillac Brougham
* 1986-1990 Chevrolet Caprice Wagon



LV2

Oldsmobile used the popular LV2, a 307 in³ (5.0 L) engine, from 1980 to 1990. It was used by every domestic GM automobile marque. Roller lifters were added in 1985.

There were two versions, the standard Y version produced just 140 hp to 150 hp (104 to 111 kW). The high-output 9 version was available in the 1983 and 1984 Hurst/Olds & 442. All LV2s feature a 4-barrel carburetor.

Y-version applications:

* 1980-1985 Buick Lesabre
* 1980-1985 Buick Riviera
* 1986-1990 Chevrolet Caprice
* 1980-1985 Oldsmobile Delta 88
* 1980-1984 Oldsmobile 98
* 1980-1985 Oldsmobile Toronado
* 1980-1990 Oldsmobile Custom Cruiser
* 1980-1981 Oldsmobile Cutlass
* 1982-1988 Oldsmobile Cutlass Supreme

9-version applications:

* 1983-1984 Hurst/Olds
* 1983-1984 Oldsmobile 442
* 1986-1990 Cadillac Brougham



LG8

The LG8 was a modern 307 in³ 5.0 L High-Output derivative of the LV2 produced from 1985 to 1987. Performance modifications included improved intake and a "hot" camshaft. It was offered in the 442 version of the Oldsmobile Cutlass Supreme. Output for the first year was 180 hp (134 kW) and 245 ft·lbf (318 N·m). The addition of roller lifters for 1986 increased torque to 255 ft·lbf (332 N·m), while lowering the RPM at which peak horsepower and torque was achieved via a change in head design.

Applications:

* 1985-1987 Oldsmobile 442
* 1985-1988 Cadillac Sedan Deville Brougham w/ Vin 9