1970½ Corvette Illustrated Series No.43

Corvettes have always had something of a split personality. Defined as a "sports car", but with musclecar straight-line, scare-you-to-death acceleration. Detroit learned early in the performance game that there's no substitute for cubic inches. But the penalty is extra weight. When the Corvette went "big-block" in '65, the split widened between the sports car and musclecar groups. The 1970 LT-1 option gave buyers the best of both worlds.

Although Zora Arkus Duntov loved the brutish big-blocks, his "ideal" for the Corvette was a balanced, mid-engine, small-block layout. After many attempts, the mid-engine Corvette just wasn't to be. His plan-B was to make a high-revving, high-performance, lightweight small-block, with a 50/50 weight distribution. The resulting LT-1 option just blew everyone away.

The LT-1 engine had about every trick part a production car could have. Designed as a high-revving performer, everything was stout. The cast-iron block had four-bolt main caps and a forged crankshaft at the bottom end. The connecting rods and pistons were forged and had 11:1 compression.
A dual-plane aluminum manifold and 4150 Holley four-barrel rated at 800 cfm handled the intake side. Over-sized valves in performance heads and solid-lifters along with a high-life cam gave the LT-1 a lumpy, "don't mess with me" idle, and cast-iron manifolds with 2.5 inch pipes. The ignition system was the latest transistor Delco model.

It all added up to 370 ponies at 6,000 rpm, and 380 ft-lb of torque. With the relative light weight of the small-block, the LT-1 was just a tick off the straight-line performance of the 454. Quarter-mile-times were around 14.10 seconds at 102 mph, with zero to 60 times around 6.5 seconds. But the best part was that because of the balanced arrangement, the LT-1 could be driven as deep into corners as Europe's finest. Some publications reported that the LT-1 was as fast, if not faster, through the curves than the 1970 911 Porsche!

The LT-1 option wasn't cheap though. At $447.60, it was $10.50 more than the '69 L71, 427/435 engine and $157.95 more than the '70 LS5, 390-horsepower 454. For 1970, Chevy sold 1,287 LT-1 Corvettes. Interestingly, the air conditioning option was $447.65, 5 cents more than the LT-1, but not available with the LT-1, as was an automatic transmission.

There was an option called the ZR-1, that was a small-block "package" version of the off-road L-88. Only 25 were ordered. For some, the 1970 LT-1 was the finest C3 Corvette made.