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Called LT-1, Zora had no idea how legendary this engine would become. After its demise in 1972, it would return in the early 1990s to power his beloved Corvette. The 1970 LT-1 is not only a powerful engine, it's also great looking with a high-rise aluminum intake, a gigantic Holley carburetor, finned aluminum rocker arm covers and a chrome open-element air cleaner with a silver and red foil label that reads, "350 Turbo-Fire 370 Horsepower." The LT-1 made most of its power at 6,000 rpm and could gleefully zoom to 6,500 rpm with nary a burp.

An important part of the LT-1 is that its development was not all mechanical, but political. The SCCA Trans-Am series mandated maximum displacement at 305 cubic inches. Ford already had a 302, but Dodge, Plymouth and even AMC did not have an engine to reach the displacement limit. To accommodate them, the SCCA allowed destroking of larger engines. This rule, which began for the 1970 season, allowed the 340-cu.in. Mopar V-8 to become 305 cubic inches. Other combinations allowed 303-cu.in. V-8s to compete. This opened the door for Chevrolet. It had the 302, but the 350 was better suited for the street than the high-strung 302. From a financial standpoint, the new 350 could be used for the Corvette and Camaro. What really made the LT-1 so special? The LT-1 had a 4-inch bore and 3.48-inch stroke. The deck height was identical to other 350s at 9.00 inches. It was inside that the LT-1 showed it was a thoroughbred. The LT-1 featured special forged TRW pistons with a high-silicone-content aluminum construction and a slipper skirt design. The advertised weight of each piston was 20.41 ounces, and the compression ratio was a healthy 11.0:1. The piston rings were similar to those found on other small-blocks. The top ring was narrow, at 5/64-inch, and was made with cast iron and a molybdenum inlay. The second ring measured the same, but was made from ductile iron with a tapered face and inside bevel. The ever-important oil ring was constructed of three pieces, including chromed steel scrapers and a stainless steel expander. The total thickness measured 3/16-inch.

All LT-1s had a pressed, chromium steel wrist pin setup, and the connecting rods were a heavy-duty 3/8-inch bolt design. The 3/8-inch bolt connecting rods were about 5.700 inches long and weighed 20.80 ounces each. The crankshaft was special too, and forged from 1018 alloy steel. These strong crankshafts were cross-drilled and internally balanced. Main and rod bearings were Moraine 400 pieces and made of premium alloy, which allowed high-rpm operation. The harmonic balancer was nodular iron and huge, at 8 inches. To protect these expensive engines, Chevrolet installed a proven wet-sump oiling system with a gear pump/rear sump setup. The pump produced 40 pounds of pressure at 2,000 rpm. The oil pans were stamped steel and, due to chassis design, the Corvette had a different pan from the LT-1-powered Z28. These pans both had special baffles, and like other Chevrolet V-8s, the LT-1 engine sent oil to the main and rod bearings first, then to the valve train and other top end components. Not to be left out, the cylinder heads featured huge, 2.02-inch intake valves and the exhaust valves measured 1.60 inches. The intake valves were made from alloy steel and the exhaust valves were made from high alloy steel and an aluminized face. The length of the intake valves measured between 4.870 and 4.889 inches, while the exhaust units measured between 4.891 and 4.910 inches. The camshaft was a solid-lifter type, with overall lift with zero lash at .4586 inches, while the exhaust lift was, again at zero lash, .4850 inches. While Chevrolet's duration figures varied at the time, the accepted duration number was 312 degrees. The duration at .050-inch tappet lift works out to 222 degrees, both intake and exhaust. The intake valves opened at 38 degrees before top dead center. The intakes closed at 94 degrees after bottom dead center. The exhaust opened at 86 degrees before bottom dead center and closed at 46 degrees after top dead center. The valve overlap was 84 degrees at zero tappet lift and the lobe centerline was advertised as 114 degrees. The pushrods were 5/16-inch blue-tip pieces, while the retainers and keepers were steel. The arms were stamped steel and the ratio was 1.5:1, with screw-in type rocker studs. The aluminum intake was cast by Winters; a high-rise, dual-plane design with a divided plenum. On top, Chevrolet workers installed an 800cfm Holley (some believe it was a 780cfm unit) with primary and secondary venturis both measuring 1.686 inches in diameter. This carburetor was similar to Holley's 4150 vacuum secondary design. The fuel bowls were "race" models, which included center-hung floats. The exhaust manifolds were cast iron and, due to varied configurations, as well as an alleged company edict that no vehicle have more horsepower rating than a Corvette, the Camaro Z28 had 360hp in 1970.

To go along with this new engine, Zora and his engineers redesigned the 1970 Corvette and solved many of the quality-control problems that plagued the 1968 and 1969 models. Some interior alterations were made to improve seating comfort and luggage access. To stop stone chips, engineers flared the front and rear wheel wells to cut back on road debris kicked up by the tires. Louvers in the front fenders were changed. In 1970, the Corvette had some new standard features, previously optional in other years, such as tinted glass, posi-traction, four-speed transmission and integrated headrests. The exhaust bezels were squared off with large, chrome rectangular extensions. Also in 1970, there were larger side marker lamps and squared-off parking lamps. If an LT-1 engine or 454 V-8 was ordered, a special hood with chrome-simulated vents was included. On LT-1 cars, the hood stripe, available in either black or white, was hand painted in two different widths. The "LT-1" lettering is self-adhesive in both colors with clear to allow the hood color to show through.

GM built 17,316 Corvettes for the 1970 model year; 10,668 coupes and 6,648 convertibles, and installed 1,287 LT-1s, about 7.5 percent of production. Initially, Chevrolet planned to offer air conditioning with this high-revving engine, but the LT-1 would throw off belts at high rpm. Air conditioning was offered only in the 1972 model year, and the LT-1 was detuned by then to 255hp. The tachometer redline was 5,600, substantially down from 1970. To keep the rpm down, GM offered only 3.36 rear gears with air conditioning in 1972.