1970½ LT-1 Corvette Illustrated Series No.44

llustrated Corvette Series No. 44 - 1970-1/2 LT-1 Corvette
"Balance of Power"

Imagine having a new Corvette with more power than a big-block, and the weight of a small-block. That was the basic idea behind the all-aluminum, 427 ZL-1 Corvette. The idea of an all-aluminum engined Corvette was first outlined in 1957 as the "Q-Corvette." What finally emerged was more than anyone ever expected.

While everyone loved the 427's power, Duntov was not happy to have 51% of the Corvette's weight over the front wheels. Some calculating showed that if the engine was completely made of aluminum, the weight would be close to a small-block. So it was decided to go-for-broke and make the ZL-1 a monster.

Duntov started with a "stock" L88 and added an aluminum block that was fitted for a dry-sump oil system, larger main bearing bulkheads, extra cylinder head bolts, 12:1 compression pistons, a new camshaft, and open-chamber aluminum heads. Cast-iron sleeves were installed in the piston bores to solve the wear problem with the aluminum block. With a set of headers, the ZL-1 made over 585 horsepower at 6,600 rpm! Since the L88 was already void of unnecessary street hardware, the ZL-1 optioned Corvette weighed in at only 2,908 pounds, about the weight of a 1957 Vette.

The big hitch for the ZL-1 was its price. The ZL-1 option alone cost $3,000 on top of the L88 option. That made the ZL-1 cost over $10,000 in 1969! That was almost twice the cost of a normal 427 street Corvette.

Only two ZL-1 Corvettes were ever made, making them the rarest Corvettes ever. Performance was amazing: 12.1 quarter mile time and 180 mph top speed. This was really Chevrolet's all-out racing Corvette!