Only Corvette ZL-1 convertible could fetch $3M

The 1969 Corvette ZL-1 Convertible is one of Chevrolet’s rarest vehicles and it’s heading to RM Sotheby’s auction in Phoenix, Arizona, auction in January.

Only two Corvettes Stingrays were equipped with the 7.0L ZL-1 V8 from factory and only one is a convertible.

The auction marks the first time a Corvette with a ZL-1 engine has been offered to the public in 30 years, and the only time a convertible with this engine has been available for purchase.

This ultra-rare Corvette was never intended for public sale. It’s anticipated to fetch between $2.6- $3 million,  which would make it one of the most expensive Corvettes ever sold. The current record is an L88-powered 1967 example that sold for $3.85M in 2014.

ZL-1-powered Corvettes were never sold in quantity to the public. This specific Corvette was purchased by drag racer John W. Maher in 1968 for nearly $10,000, the equivalent of approximately $87,000 when adjusted for inflation.

An extensive set of options nearly doubled its base MSRP $4,781. Maher purchased the Corvette with help from his friend and fellow race car driver Don Yenko. The latter was instrumental in proposing the idea of a ZL-1 V8 in a Corvette.

Maher also had the vision of pairing the ZL-1 engine with GM’s M40 transmission,  capable of strong, full-throttle launches. GM eventually built Maher’s ZL1 Monaco Orange colored Corvette equipped with both the ZL-1 engine and M40 transmission.

Chevrolet’s near 70-year production run of the Corvette has seen countless iconic special editions — none of which have an engine as rare as that in the Stingray ZL-1 Convertible.

Besides its monstrous 427 cubic inches, the iconic V8 is homologated from CanAm racing and is more refined than any V8 of its era. The ZL-1 engine is based off of the L88 big-block in other high-end Corvettes during this Stingray’s time but is lighter, has improved pistons, a better crankshaft and higher lift camshaft. 

Later vehicles using the engine were produced with open chamber cylinder heads for a boost in horsepower. This specific example, however, retains the pre-production closed chamber heads.

Such upgrades over mass production Corvettes means the ZL-1 engine was rated at 560 horsepower making this the most powerful engine Chevrolet produced at the time. That’s also five horsepower more than the highest-trim Corvette Stingray currently sold.

The exceptionally rare Corvette was designed strictly for racing, meaning the winning bidder at this month’s Sotheby auction will have to do without a radio, air conditioning, heat, power windows, and power steering. Even the fan shroud was taken out as it obstructed airflow.

ZL-1-powered Corvettes are, however, also equipped with the heavy-duty suspension package, a Positraction rear axle, and transistorized ignition.

The race-ready Corvette was used heavily during Maher’s ownership in drag racing events in addition to auto crosses and hill climbs. It was so successful he labeled his vehicle as “winning automatically.” The ZL-1’s original short block was blown less than a year after Maher took delivery where it was replaced under warranty by Chevrolet.

Recently the vehicle underwent a full restoration by Kevin Mackay’s Corvette Repair Inc., among the most prestigious Corvette restorers. Mackay and his team found that the blown engine was the only damage that had occurred during Maher’s 39-year ownership.

The Corvette was immediately entered in the Bloomington Gold show in Champaign, Illinois where it was awarded Bloomington Gold certification. Such an award means the vehicle remains within 95% original condition as it left the factory in 1968.

For more information regarding this ZL-1 Corvette, click here.

Mason Bloom is a reporter for TheWeeklyDriver.com. When he is not writing about industry news, new car reviews or covering live motorsport events, he is a sophomore at Aptos High School on the California central coast.