http://www.pontiacsafari.com/EngineCooling/index.htm
http://community.fortunecity.ws/silverstone/pontiac/101/tech/cams.htm
http://enginefacts.com/pontiac389.php
http://garage.grumpysperformance.com/index.php?threads/some-pontiac-related-links.4125/#post-42587
389 V8 Engine
The Pontiac 389 V8 was first introduced in 1959 and would become one of the most popular engines of the muscle car era. The engine evolved from the Pontiac 370 in which the stroke was increased. There were a lot of changes to the 389 during its eight year production run which gained the engine even more notoriety. Most experts agree that the 389 was one of the key factors in starting the muscle car wars of the 60s.
One of the first major changes for the 389 came in 1960 when Pontiac stopped using its “reverse flow” cooling option for the powerful V8. From 1955 to 1959, Pontiac had used a cooling system (and some GM motors still use it today) where the coolant was sent to the heads first and then down through the block. The idea behind “reverse flow” was to keep the heads cooler because of the large problem with engines in the 50s burning up and warping the valves. By 1960 GM had started using harder and more reliable valves and seats for their engine heads which let them do away with the “reverse flow” cooling method. For more information on “reverse flow” and why Pontiac stopped using it check out this interesting site.
All Pontiac V8s from 1955 to 1959 were reverse cooled, known as the "gusher" cooling system. It was removed from the design for the 1960 model year because designers moved the generator and the power steering pump from atop the front of the engine down to the front of the heads to accommodate a lower hoodline. However, the 1959 389 engines had the generator in front of the heads with reverse flow cooling still in use. This suggests that the cost of the reverse cooling was the reason for the change to "equa-flow" cooling.
The 389 was also the first engine by Pontiac to come with the S.D. (Super Duty) option. If you are lucky enough to find a 389 S.D. engine then you will have quite an impressive setup such as a four bolt main engine block and a forged steel crankshaft and connecting rods. These Super Duty 389 engines were mainly used for NASCAR racing but a small amount of them offered for sale to the public in order to meet NASCAR standards.
Another impressive version of the 389 introduced in 1959 was the Tempest model. The Tempest 389 engines were also known as “420-A” motors and came with higher compression as well as better performance options. These engines were available up through 1962 and produced up to 348 horsepower which was the highest power output a factory 389 engine would ever see with the Tri-Power carb setup.
The 389 Pontiac motor also has the coveted award as being the first engine used in one of the most famous muscle cars of all times, the Pontiac GTO. The GTO is considered by many automotive enthusiasts to be first real muscle car on the block even though it’s a discussion that could be debated. By the end of 1966 the last of 389 engines rolled off the assembly line to be replaced by the Pontiac 400 but it didn’t leave without leaving a lasting legacy on the automotive world that will never be forgotten.
Today, engine parts for the 389 are in abundant supply especially if you are looking to push up the factory horsepower. Most any performance auto part stores will have quite a nice inventory of carburetors, headers, cams and many other engine parts that can really give your 389 quite an increase in power and performance.
Pontiac 400 V8 Engine
The Pontiac 400 6.6 Liter engine was first introduced in 1967. This version of the Pontiac V8 engine was used in the GTO, Firebird, and the Trans-Am Firebird.
The 400 was inspired by the Pontiac 389 V8 and proved to be the last Pontiac engine with closed chambered heads. At the start of the 1970s, the 400 V8 generated more than 300 horsepower, but decreased to 180 horsepower by the time the last 400 engine was produced in 1978. The special edition black and gold Trans Am made famous by Burt Reynolds in the Smokey and the Bandit movie franchise increased Firebird sales in 1977 and 1978 and made the 400 V8 quite popular. Even though production of the 400 had ceased, 1979 Pontiac models still featured the 400 engine due to large stockpiles left over from the previous year.
In 1980, Pontiac decided to use the Pontiac 301, 4.9 V8 engine to replace the 400. Sales and the new engine’s performance failed miserably and the 301 was no longer offered by Pontiac after 1981.
Pontiac 421 V8 Engine
In 1961 Pontiac continued to push the horsepower upwards with the release of the 421 engine. As with all other Pontiac V8 motors that evolved from the 316 V8, the 421 was simply a bored out and stroked version of the popular Pontiac 389 V8. What was most interesting about the 421 engine in the beginning was that it was a dealer installed option only known as the SD (Super Duty) 421. These motors were built mainly for NASCAR or other racing purposes and were equipped with all the extra racing goodies that people were looking for. A Pontiac SD 421 came with forged steel rods and crankshafts for extra durability. In 1961 and 1962 they were available with either one 4 barrel carburetor or a dual 4 barrel carburetor setup depending on whether the buyer wanted to head to the racetrack or drag strip.
By 1963 Pontiac decided it was time to release the 421 V8 officially to the general public and the motor would continue to be available until the end of the 1966 model year. The 421 SD Tri-Power engine offered during these years produced the highest horsepower of any motor in the Pontiac V8 lineup at 376 bhp. There were a few 1962 Grand Prix models that came with a 421 SD from the factory so if someone is lucky enough to have one today then they have a car that is probably worth some decent money simply because of the rarity of these models.
http://community.fortunecity.ws/silverstone/pontiac/101/tech/cams.htm
http://enginefacts.com/pontiac389.php
http://garage.grumpysperformance.com/index.php?threads/some-pontiac-related-links.4125/#post-42587
389 V8 Engine
The Pontiac 389 V8 was first introduced in 1959 and would become one of the most popular engines of the muscle car era. The engine evolved from the Pontiac 370 in which the stroke was increased. There were a lot of changes to the 389 during its eight year production run which gained the engine even more notoriety. Most experts agree that the 389 was one of the key factors in starting the muscle car wars of the 60s.
One of the first major changes for the 389 came in 1960 when Pontiac stopped using its “reverse flow” cooling option for the powerful V8. From 1955 to 1959, Pontiac had used a cooling system (and some GM motors still use it today) where the coolant was sent to the heads first and then down through the block. The idea behind “reverse flow” was to keep the heads cooler because of the large problem with engines in the 50s burning up and warping the valves. By 1960 GM had started using harder and more reliable valves and seats for their engine heads which let them do away with the “reverse flow” cooling method. For more information on “reverse flow” and why Pontiac stopped using it check out this interesting site.
All Pontiac V8s from 1955 to 1959 were reverse cooled, known as the "gusher" cooling system. It was removed from the design for the 1960 model year because designers moved the generator and the power steering pump from atop the front of the engine down to the front of the heads to accommodate a lower hoodline. However, the 1959 389 engines had the generator in front of the heads with reverse flow cooling still in use. This suggests that the cost of the reverse cooling was the reason for the change to "equa-flow" cooling.
The 389 was also the first engine by Pontiac to come with the S.D. (Super Duty) option. If you are lucky enough to find a 389 S.D. engine then you will have quite an impressive setup such as a four bolt main engine block and a forged steel crankshaft and connecting rods. These Super Duty 389 engines were mainly used for NASCAR racing but a small amount of them offered for sale to the public in order to meet NASCAR standards.
Another impressive version of the 389 introduced in 1959 was the Tempest model. The Tempest 389 engines were also known as “420-A” motors and came with higher compression as well as better performance options. These engines were available up through 1962 and produced up to 348 horsepower which was the highest power output a factory 389 engine would ever see with the Tri-Power carb setup.
The 389 Pontiac motor also has the coveted award as being the first engine used in one of the most famous muscle cars of all times, the Pontiac GTO. The GTO is considered by many automotive enthusiasts to be first real muscle car on the block even though it’s a discussion that could be debated. By the end of 1966 the last of 389 engines rolled off the assembly line to be replaced by the Pontiac 400 but it didn’t leave without leaving a lasting legacy on the automotive world that will never be forgotten.
Today, engine parts for the 389 are in abundant supply especially if you are looking to push up the factory horsepower. Most any performance auto part stores will have quite a nice inventory of carburetors, headers, cams and many other engine parts that can really give your 389 quite an increase in power and performance.
Pontiac 400 V8 Engine
The Pontiac 400 6.6 Liter engine was first introduced in 1967. This version of the Pontiac V8 engine was used in the GTO, Firebird, and the Trans-Am Firebird.
The 400 was inspired by the Pontiac 389 V8 and proved to be the last Pontiac engine with closed chambered heads. At the start of the 1970s, the 400 V8 generated more than 300 horsepower, but decreased to 180 horsepower by the time the last 400 engine was produced in 1978. The special edition black and gold Trans Am made famous by Burt Reynolds in the Smokey and the Bandit movie franchise increased Firebird sales in 1977 and 1978 and made the 400 V8 quite popular. Even though production of the 400 had ceased, 1979 Pontiac models still featured the 400 engine due to large stockpiles left over from the previous year.
In 1980, Pontiac decided to use the Pontiac 301, 4.9 V8 engine to replace the 400. Sales and the new engine’s performance failed miserably and the 301 was no longer offered by Pontiac after 1981.
Pontiac 421 V8 Engine
In 1961 Pontiac continued to push the horsepower upwards with the release of the 421 engine. As with all other Pontiac V8 motors that evolved from the 316 V8, the 421 was simply a bored out and stroked version of the popular Pontiac 389 V8. What was most interesting about the 421 engine in the beginning was that it was a dealer installed option only known as the SD (Super Duty) 421. These motors were built mainly for NASCAR or other racing purposes and were equipped with all the extra racing goodies that people were looking for. A Pontiac SD 421 came with forged steel rods and crankshafts for extra durability. In 1961 and 1962 they were available with either one 4 barrel carburetor or a dual 4 barrel carburetor setup depending on whether the buyer wanted to head to the racetrack or drag strip.
By 1963 Pontiac decided it was time to release the 421 V8 officially to the general public and the motor would continue to be available until the end of the 1966 model year. The 421 SD Tri-Power engine offered during these years produced the highest horsepower of any motor in the Pontiac V8 lineup at 376 bhp. There were a few 1962 Grand Prix models that came with a 421 SD from the factory so if someone is lucky enough to have one today then they have a car that is probably worth some decent money simply because of the rarity of these models.
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