The first version of the big block Chevy was introduced in 1958 in the name of W- Series and it was designed to be used in light trucks and passenger cars. It has remained in the market for seven years from 1958 to 1965 with three displacement options. And these three options are 348, 409 and 427 cubic inches. The initial product was made from cast iron. And in this version, the engine block had two –bolt main bearing caps, 4.84-inch bore centers, and a lubricant system.
And the specialty of this W-series was that the combustion chamber of this engine was placed in the upper chamber of the cylinder unlike the other machines of this category as in those machines the combustion chamber was placed in the head. At that time, this machine was well-liked and was the first choice in the USA since it was working well for heavier cars and trucks.
And after 1965, a new version of this product came into the market with some more developed features and technologies and also with a new name Mark IV series. And there were some difference in the placement of the valves and shape of the combustion chambers in both these versions. Though the valves were used as the displaced arrangement like the previous one, but here those were more inclined so that they would open away from the cylinder walls and combustion chamber. This change made a major improvement in volumetric efficiency at high RPM and a considerable increase in power production at racing speeds.
The new version had also made changes in the placement of the combustion chamber. Instead of making it straight like the first one, they entered the combustion chamber at an angle relative to the cylinder centerline and that proved very helpful for high RPM performance. Like the previous one, this frame was also made from iron cast and here the side oiling lubricant system was more efficient and was providing maximum oil flow to the connecting rods. And this new version had also three displacement options and these three options are 366, 396, and 402 Cubic inches. And this product remained in the market from 1965 to 1972.
Some other new versions like 427, 454, 502, 572 etc. had come to the market with different features and developed technologies. All these products had some special features and also popular for a certain period of time.
But in these fifty-eight years, this motor engine has made a significant improvement and also has come with so many significant features to develop its performance and to meets the market strategy and customers. It has also different replacement options. Here are the some of the features of its developed 496 Chevy motor.
Features of the 496 motor
• Four bolt main.060 over block
• Four hundred eighty @five thousand two hundred rpm
• New four thousand forty forged connecting rods
• 9:1 compression ratio
• New one hundred sixty-eight flex plate
• Two peace passenger side dipstick and rear seal
• New cast steel crankshaft externally balanced, 4.250" stroke
• Five hundred fifty ft.-lbs. @ four thousand rpm
• Hypereutectic flat top pistons
• Rotating assembly balanced to within two grams
• Timing cover and Chrome valve covers
• Screw-in studs and guide plates
• Melling high volume oil pump
• Power + Crosswind dual plane aluminum intake manifold
• GM cast iron oval port heads
• New HEI distributor
• Hydraulic flat tappet camshaft
Above are the essential features of the 496 motor if one chooses some other Chevy product then the features will be slightly different and all of the products have some distinctive features to deal with a specific problem. So, while choosing a big block Chevy, always try to go through all its features to find a suitable one.