Thread: difference between small and big block?

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What is the difference between a small block and a big block motor ?

As you'd expect from the descriptive references, a small block is a physically smaller motor than a big block and weighs less. It is also smaller in displacement. There is a crossover at about 400 cubic inches in the Chevy lineup, that's the largest small block and a 396 is the smallest big block. There are smaller big blocks, but they are obscure truck motors that none of us use for performance purposes.

Small block Chevys came in displacements of 265, 267, 283, 302, 305, 307, 327, 350 and 400.

Big block Chevys came in displacements of 396, 427 and 454. There are some late model 502 big blocks available also.

All these small block motors I've referenced are 1955 to 1986. There are some others that have been built since '86 that I am not familiar with, maybe someone else can jump in and help.

a very unccommon 262, they were only used in some 1979-1981 Monte's I belive, the 267 was the most common for car motors those years. Newer SB's would be a 5.3L 293 used in trucks and some cars.

Another rare displacement I recall reading about (never saw one) was a 409 cid. I cant remember the body name but it resembled an early Impala.

As far a modern technology, the automakers seem to be using litres as identifiers, especially in small block V-8's. We all know the familiar GM 5.0 and 5.7. But now adays we see more of the smaller displacement 4.8 and 5.3 (trucks) . There is a 6.0 GM and I'm not sure if that is a small block or not. Most of GM rear drive V-8 passenger cars are still using versions of the tired and true 5.7, with the Corvette getting a cid change just recently.

I wonder if Ford started it all with the famous 5.0 Mustangs?
I still like the sound of 302 boss though!

Most of GM rear drive V-8 passenger cars are still using versions of the tired and true 5.7, with the Corvette getting a cid change just recently.


Excuse me, that should read TRIED and true.

"The 5.7ltr. 350cid GM small block. In our opinion, the best pushrod V-8 ever manufactured for production vehicles in the world." Car and Driver.

"Excuse me, that should read TRIED and true"

I think tired and true is probably more appropriate.

streeter, the 348 was introduced in 1958 and was the first big block motor. It was complimented a couple of years later with its big brother, the 409. I left them out of the lineup because you seldom see one of them anymore, unless it is in a restored Impala. The 409/4-spd. was probably the first Chevy muscle car motor/trans. Although it was basically a truck engine, Chevy offered them in the Impala from '61 to '65.

Yep they have been around for a while. So has Jack Daniels and its still good.

Small block and big block comes largely down to deck height. Well its true that big blocks usually have larger mains and longer stroke, some big blocks were made from adding extra material to the existing small block platform. Good example, Big block Oldsmobile

Hey S10, Ford actually started it long before the 5.0 Mustangs. In 67 (maybe it was 66?) Ford had a Galaxie with the motor designated as a 7 litre.

While on the subject of 348/409, don't forget Chevy's first Nascar monster, the original 427.

Ford had the first 427.

nystreetscene - Chevy small vs big blocks can easily be recognized by the much wider cylinder head on the big block than the small block.

I'm sure there are other quick ID points, but I find that the easiest for me.

Not sure about - the other mfgs.

Bert

Originally posted by Ives Bradley
Ford had the first 427.

427 Cammer


1965








Comments: Without a doubt the most powerful engine ever made, the Ford 427 Cammer was developed with the intention of taking on Chrysler's Hemis. Ford gave the 427 block new heads with hemispherical combustion chambers. To cap that, they fitted overhead camshafts -- one per cylinder bank -- which gave the engine its name and allowed it to rev to an unheard of 7,500 rpm. With the regular single four barrel carb, the "cammer" put out 616 bhp, but with dual four-barrels, it produced a massive 657 bhp. With this kind of power, the "cammer" 427 was totally unsuitable for street use. These engines were not sold to the general public, but about 50 examples were built, mostly for professional drag racers. Because of the low production volumes, NASCAR refused to accept the engine as a regular production option, and thus Ford couldn't use the engine to combat the Hemi's. This sealed this engine's fate and Ford discontinued it after 1965.

Ratings:
1x4bbl: 616bhp @ 7500rpm. 2x4bbl: 657 bhp @ 7500rpm, 550 lb-ft.

Phew! feels like I'm doing a hundred, (my pulse anyway) just reading that!

The first Ford 427 came out in 63 1/2. Topoiler/Centeroiler as they are known. The First Cammer prototype was late in 64.