Small ou big block ??

Paul76 a écrit:en passant, cé pas un big block si cé plus petit kun 402, non?

si je fouille bien dans ma mémoire, un 350 amériquain , cé bien un big block

396 SB ou BB??

427copoz a écrit:

396 SB ou BB??

le 396 Chevy est un Big Block

Salutations

J'imagine que 427copoz à la réponse à ça!

philr a écrit:J'aimerais aussi être éclairé sur les suivants:

les 402 Chevrolet, c'était quoi?? Et les 403 Olds, des small blocks si je me trompe pas?
Et les 389 de Pontiac? Les 383 et 400 Mopar? Les 390 Ford?? 401 AMC?
Et surtout (puisque j'en possède un!) un 401 (ou un 425) de Buick, est-ce que c'est considéré comme un small block ou un big block? Je demande ça parce que malgré qu'ils soient pas mal plus pesants que les 455 de Buick, ils sont très semblables aux 364 et aux 322...

J'imagine que 427copoz à la réponse à ça!

427copoz a écrit:Salut philr

J'imagine que 427copoz à la réponse à ça!

c'est un test
d'évaluation ou quoi
et avec quelque trape a souris en prime

Salutations

Non, mais j'aimerais bien voir tout ça démêlé! Par exemple, un 403 de Olds, j'ai entendu dire que ça s'apparentait plus à un 350 qu'un 455 et là Dom dis que c'est un big block.

pour les block AMC y a pas de small ou de big , parce qu'il y a qu'un seul model de block de 1967 à 1992 , et il est percé et stroké différement sois 290.304.343.360.390.et 401cid.
des petits changements ont été fait en 1970 sur les block (hauteur du deck) et les vis des têtes .

A small-block engine is a North American V8 in a family of engines which generally have less than 6 liters (360 in³) of displacement, [/b]although some derivatives have grown larger (up to 427 in³, 7.0 L). A 505in³, 8.3 L V10 is produced by Chrysler, a derivative of the LA engines. Larger families of engines are called big-blocks. The distinction came about in the late 1950s when the large full-size cars needed a bigger V8 than the smaller mid-size and compact cars - though consumers wanted a V8 under the hood, the recession of the late 1950s provided some of the earliest American awareness of fuel economy. Prior to that point, manufacturers normally had only one V8 engine line.

The term is normally used only for engines from the "Big Three" (Ford Motor Company, General Motors, and Chrysler Corporation) since the other companies did not keep two V8 engine size families. However, it is sometimes used for the more modern and compact V8s produced by others, such as Studebaker.

The term "block" refers to a piston engine cylinder block, which is the lower portion of a piston engine containing the pistons and cylinder bores.

Although a small-block V8 generally has a smaller displacement than the equivalent big-block, a small-block engine can be built to develop significant amounts of power. Additionally, many small-block engines were more advanced technologically than their big-block counterparts, and were much lighter and smaller. Innovations such as aluminum heads and blocks generally came first to small-blocks. From a new car buyer's standpoint, they tended to offer an acceptable compromise between horsepower and economy, so they were a popular option instead of the basic I6 or V6 engine base model. Because of their attractive combination of popularity (and therefore low-cost availability) coupled with good performance, good fuel economy and light weight, they were often preferred in racing and sporting applications. Many hot rods and custom cars are fitted with small-block V8s, particularly the GM (Chevrolet) 350 engine and the Ford 351 Windsor.

There are some cases in which small-blocks seem to encroach upon big-block displacements; in these cases it is most important to keep in mind that small-block and big-block refer to engine families, not simply displacements. For example, engines ranging from the 4.8 L Vortec 4800 to the 7.0 L LS7 are all GM small block V8s, and share the same general external dimensions. The LS7 achieves enormous displacement by having a very large bore and stroke in the same compact block as previous small-blocks, but has very little space between cylinders. This would not be acceptable in a truck engine, and was not possible forty years ago. As a result, 7.0 L is a displacement ordinarily reserved for big-blocks, which can achieve it with fewer compromises in reliability and less engineering effort. A 7.0 L big block, like the 427 Chevy first seen in 1966 Corvettes, is a much larger engine externally and shares external dimesions with engines ranging from the 6.5 L 396 to the 8.1 L Vortec 8100.

A big-block engine is a North American V8 in a family of engines which generally have greater than 5.9 L (360 cubic inches) of displacement;

factory engine sizes reached a peak of 8.2 L (500 cubic inches) in Cadillac's 1970s range. Since then manufacturers have responded to the need for superior engines, as well as the need to replace surviving worn-out, decades-old big-block racing engines which have been rebuilt too many times. In 2002 General Motors released the carbureted Chevrolet 572 crate engine (9.4L), available for installation in most vehicles which have enough room under the hood, both in a 620 hp street version, which runs on premium gasoline, and a 720 hp version, which requires racing fuel. Mopar (Chrysler) recently released the 528 Hemi (8.7L) and 540 (8.8L) crate engines. Both of these incorporate modern hardened metals and are able to run on unleaded gasoline.

Smaller V8 engines are known as small-blocks; some members of small-block engine families may exceed 6 L, blurring the distinction somewhat. The distinction came about in the early 1960s when the large full-size cars needed a bigger V8 than the smaller mid-size and compact cars. Before that, manufacturers normally had only one V8 engine line.

The term is normally used only for engines from the "Big Three" (Ford Motor Company, General Motors, and Chrysler Corporation) since the other companies did not keep two V8 engine size families.

Big-block V8s were most commonly used in full-size and luxury cars, rather than performance vehicles. Thus, they were commonly tuned and built for smooth, low-end torque to get heavy cars rolling and effortlessly cruising. Many big-block engines were less technically sophisticated than their small-block counterparts, and their power-to-weight ratios were often lower. Today of course big-block engines are used in racing.

However, they did see performance applications. Performance-tuned big-blocks were used in NASCAR racing, and homologation requirements saw these engines sold for road use. Because of NASCAR's 7 L engine size limit, many high-performance big-block engines, like the Chevrolet's 427, Ford's 427, and Chrysler's 426 Hemi engines, were built to this size. In the mid to late 1960s, the explosion of the muscle car market saw performance big-blocks fitted to intermediate-size cars. Some used derivatives of the racing engines, but in addition performance versions of former luxury motors were produced.

After the 1973 oil crisis, the days of the big-block in passenger cars were numbered. By the end of the 1970s, they were no longer to be found. However, these engines remained in use in pickup trucks and other non-car uses. Currently, only GM offers big-block V8s in its trucks; Ford and Chrysler essentially replaced their big-blocks with stretched V10 versions of their small-block engines in the early to mid 1990s.

Greaser a écrit:Small bloc est simplement une famille de moteur et ses derivees.

musman a écrit:Un 390 de Ford est un Big Block.

Small Block Identification

A small block measures 12" between the heads at the manifold base.

Facing the front of the engine, at the top surface of the timing chain area, to the left of the oil fill tube, there is a code about 1.5" high followed by the casting number. A letter indicates a big block, a number indicates a small block.

Big blocks have a little hump in that area, whereas the small blocks have a completely flat shelf.

Small blocks from 1977 onward will have the CID or liters cast in large numbers right above the center core plug. The engine VIN number will also be cast onto the side of the block.

From the outside they don't look different at all because the 260, 307, 330, 350, and 403 are all the same basic block. But externally the distributor, valve covers, water pump, front cover, oil pan, carb, etc are the same.

Big Block Identification

A big block measures 14" between the heads at the manifold base.

Facing the front of the engine, at the top surface of the timing chain area, to the left of the oil fill tube, there is a code about 1.5" high followed by the casting number. A letter indicates a big block, a number indicates a small block.

Big blocks have a little hump in that area, whereas the small blocks are flat the whole way across.

When Chevy engineers established the dimensions of the small block, they never dreamed that someday it would displace more than 400 cubic inches. At the time, there were no plans to enlarge the displacement much beyond the original 265 cubic inches. In fact, the engine was initially planned to displace 260 cubic inches with 3.75-inch bores and a 2.93-inch stroke. But they decided to round off the stroke to an even three inches, which pushed the displacement up to 265.

As casting techniques improved, Chevy engineers realized the small block had a lot of potential for growth. They could increase the bore size and the stroke to offer more displacement and power for larger cars or more performance. The 265 soon became a 283, then a 327, then a 350 and eventually a 400 with other sizes in between (302, 307, etc.). The flexibility of the original block and heads is one of the reasons the engine remained in production for so long and was produced in so many different configurations.

The interchangeability of parts, namely the cylinder heads, block, pistons and cranks, also allowed this engine to be built many different ways and to be installed in many different vehicles. The growing volume of engines that were being produced also meant that the small block Chevy V8 was plentiful and cheap, making it a natural choice for hot rodders, racers and aftermarket performance products. Eventually, it would become the most popular performance and racing engine of all time.

The compact size of the block (21.75 inches long and only 9 inches high from the oil pan rail to the cylinder heads) allowed the engine to fit almost anything. The block only weighed 531 pounds, which was 41 pounds less than Chevy's in-line six-cylinder engine. This too, was a big advantage and attraction for many hot rodders and racers. The new block also required only 12 casting cores, compared to as many as 22 for other manufacturers' blocks at the time. This reduced the cost of the engine and allowed the cylinders to be cast with greater precision.