Perhaps the most balanced engine for the 1968 and 1969 model years was the L89 big-block. Based on the 435-horsepower L71, the L89 option uses Chevrolet’s rare big-block aluminum heads to further aid the breathing enabled by its solid-lifter cam, aluminum intake and triple 2-barrel Holleys; the L89’s additional power is extraordinary. Chevrolet started out with a four-bolt main, cast iron block, then engineers crafted a pair of high flow, lightweight, aluminum heads to top it off.
Resting between the heads was an aluminum tri-power intake manifold with three Holley Model 2300 carburetors. While the L89 was rated at the same 435 horsepower as the iron-head L71, the L89 was known to produce slightly more power thanks to its larger exhaust valves (1.84 inches versus 1.72 inches). It also weighed about 75 pounds less, thus reducing unnecessary weight from the front end and helping handling characteristics.
The option didn’t come cheap though, the L89 aluminum head option cost $832.05 (which included the normal L71 engine in 1968). Its performance was worth the money though, with 0 to 60mph over in just 4.2 seconds and 0 to 100mph taking just 8.0 seconds.
A limited production of only 390 L89-configured Corvettes rolled off the assembly line in 1969, and one of these rare specimens is set to go under the hammer at RM Sotheby’s auction on January 25. This Daytona Yellow L89 Convertible was originally ordered by Steve Honnel, a drag racer from Auburn, Alabama, through Fort Walton Florida’s Hood Motor Company. It featured a tasteful array of options, including power brakes, power steering, a 3.55 Posi-Traction rear axle, full-transistor ignition system, M21 close-ratio transmission, AM/FM radio, headrests, and an auxiliary hardtop.
Although initially powered by the numbers-matching L89 engine, Honnell eventually replaced it with a drag-prepped LS6 V-8, signaling the Corvette’s dedicated drag racing purpose. Because of it being converted as a drag racer, the car was never was never titled or registered, accumulating a mere 361 miles, primarily from quarter-mile sprints enjoyed between 1969 and 1977 before being consigned to storage alongside its original engine.
In 2005, Honnell sold the forgotten gem to Danny and Kenneth Watkins, leading to an eight-year painstaking restoration to its original specifications in collaboration with Honnell. The only significant addition made by the Watkins was a correct-for-1969 N14 exhaust system. The car, maintaining its originality, retained all major numbers-matching powertrain components.
Following restoration, chassis number 710749 underwent National Corvette Restorers Society judging, earning a Second Flight Award in April 2013 and Top Flight recognition in April 2014. Accompanied by a wealth of original documentation, including a hand-signed letter from John Z. DeLorean, this cherished L89 Convertible has been a registered member of Kevin Cavanaugh’s L89 registry for over 30 years.