Top 5 Small Block Chevy Engines of the Muscle Car Era
The Small Block Chevy Engine Was a King
There have been many great Chevy Gen I small block engines so it was tough for us to pick a top 5. Let us know if you agree or if you’re favorite’s not listed here.
Before we start, let’s all agree on the nomenclature. The pool of Chevy engines from which we selected are all considered Generation I small blocks, manufactured from 1954 through 2002, and feature the original coolant flow pattern through the cylinder heads. So no use bringing up the Corvette LT-5 engine.
Surprisingly, the little 5.35 L Chevy L-84 V8 was the most powerful production small block Chevy engine available for nearly three decades. The 327 was first introduced in 1962 with a larger 4.00-inch bore and shorter 3.25-inch stroke. At the time, the 327 was the largest displacement small block available, and by 1964 the higher-compression, L-76 4-barrel carburetor version was producing 365 horsepower. To further raise the stakes, for the 1964 and 1965 Corvettes, Chevrolet offered an L-84 version of the 327 topped with the latest iteration of the Rochester mechanical fuel injection system. While simplistic compared to modern computer-controlled management systems, the Rochester fuel injection system offered significant top-end power improvement over a carburetored L-76. The mechanical injection setup, along with 11:1 compression, 461 cylinder heads with large diameter valve, “Duntov” 30-30 solid lifter camshaft pushed the L-84 to 375 horsepower
At 1.15 hp-per-cubic-inch, the L-84 remained the most powerful Generation I small-block by displacement, and the most powerful naturally-aspirated single-cam small-block until the arrival of the Generation III LS6 engine in 2001.
Unfortunately, the Rochester system was expensive and few customers ordered the L-84 for their Corvette, preferring the L-76 for its lower price and then in ’65 the 425 hp 396 could be purchased for less than the L-84. The L-84 was in production for just two years.
The 327 L-79 had the distinction of being the first performance small block Chevy with a hydraulic cam, essentially the solid-lifter L76 motor with the 30-30 cam and lifters swapped out for the #151.
The two motors featured the same bore and stroke, compression ratio, forged pop-up pistons, 2.02 Corvette cylinder heads, and aluminum intake manifold. The L79 produced 350 hp. The beauty was that driveability was improved and maintenance was vastly reduced, with a very small loss in performance of less than 15 hp.
Like the Ford Boss 302, this motor had but one purpose: to win the SCCA Trans-Am Championship. It powered Camaros against the Mustangs, as well as Javelins, Barracudas, Challengers and even a Firebird. The engine was created by (basically) installing a 283 crankshaft into a 327 block to create a motor with a four-inch bore and a three-inch stroke displacing 302 cubic inches, just under the 5.0L class limit. The focus of this motor was not really torque, but of being able to run at high revs, as Trans Am races began with rolling starts and most turns at the tracks of that time were mid- to high-speed corners. To develop this motor, Chevy engineers applied all the hardware originally designed for the larger L76 327 (which shared its bore), including high-flow, big valve 461 cylinder heads, a solid lifter 30-30 camshaft, shot-peened rods, and a high-rise aluminum intake topped with a Holley 780 four-barrel carburetor.
The LT-1 is in the minds of many the ultimate Generation I small block. It was first introduced in 1970. The LT-1 displaced 350 cubic inches (5.7 L) and used solid lifters with the 178 performance camshaft, 11:1 compression ratio and topped with a 780 CFM Holley four-barrel carburetor feeding a unique aluminum intake manifold, a Delco transistorized ignition system and a low-restriction exhaust factory rated that produced 370 hp in the Corvette (with its superior exhaust). The LT-1 was available in the Corvette, and Camaro Z28.
Unfortunately, the party lasted only a year. For 1971, the power was cut to 330 hp due to a reduced 9:1 compression ratio. The last year of the LT-1 was 1972 and it so completely de-tuned for emissions and economy it’s not worth mentioning.
Ok, this is a bit of a cheat as this engine never installed in a Chevy muscle car. It is, however, a genuine Generation I small block – in fact, the very last one. Displacing 5.7L and built for ’96 – ’99 pickups and Suburbans, the Vortec is a surprisingly powerful and docile engine. The L31 heads are very similar to those used on the C4 Corvette and are often used as an upgrade to other small blocks. While it ended production in 2002, making it the last of a line of original small blocks that started in 1954, it remains available through Chevy Performance as a 350 HP (remember that’s NET, not the GROSS HP of the 1960s) with electronic fuel injection packaged to look a bit like the Rochester unit of the L-84. I guess what goes around comes around.
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