As Corvette sales fell in 1970 to 17,316, all but half of the 1969 numbers, there was big news from Chevrolet that would eventually be the highlight of the C3 Corvette era.
A new small block was available as a Corvette option. The RPO LT1, a solid lifter 350 cubic inch small block was conservatively rated at 370 horsepower and 380 ft. lbs. of torque@ 6000 rpm.
In 1970 you could order RPO LS5, a new 454 cubic inch big block with 390 hp. For an additional $289.65, by comparison the high winding RPO LT1 would set you back $447.60. You would spend $157.95 more for 104 less cubic inches, and, 20 horsepower and 140 ft. lbs. of torque less. Most buyers didn’t think it was worth it. Subsequently, the big blocks out sold the LT1, hence the rarity.
In the end though, the LT1 outperformed the big block. The LT1 delivered less curb weight, less forward weight bias, a shorter stopping distance, and overall better balance, not to mention cheaper insurance rates.
The only thing the LT1 couldn’t do was out ET the big block. Unless you were drag racing only, you were better off with the ideal mix of acceleration and handling of the LT1. With its unique stripping on the hood, only 1287 were produced.
The LT1 Corvette was the last Radical Corvette that Chevrolet offered for the next 20 years, signaling the end of big power Corvettes for a long time. It wasn’t until 1990, that a small block produced more horsepower.
From a factory built standpoint, the LT1 it was the last Radical Corvette. The Corvette descended into the dark ages, which is the early emissions era. This was the last year for the high compression engine, as unleaded gasoline was in the future.