There are a lot of obscure holidays out there that, for better or worse, allow seemingly normal people to, as they say, “let their freak flags fly.” Star Wars fans love to nerd out on May the 4th (be with you), math geeks (and Village Inn) are all about Pi Day (3.14), and today is extra special for Bow-Tie aficionados. Even in the storied pantheon of Chevrolet powerplants, one displacement stands above the rest, and, on 4/27, we get to celebrate the 7.0-liter monsters that have been sending all of their glorious firepower to the rear wheels of our favorite cars since 1966!
The Original: 1966 Corvette 427
One year after the first Big-Block was shoehorned between the front fenders of a Chevrolet’s halo car, that 396 was replaced with an even bigger 427, and a legend was born. The ’66 427 was available in two flavors; a stout “L36” with 390-horses and the fire-breathing 425-horse L72. A total of 5,116 ‘Vettes were ordered with the 390-horse 427 in the inaugural year of production, at an upcharge of $181.20. The $312.85 L72 accounted for 5,258 units in 1966.
427s Gone Wild: 1967-69 Corvette
The number of 427s in the Corvette order guide more than doubled in 1967. The 390-horse remained, and it was joined by a new 400-hp variant, while the L72 was replaced by a new 435 HP L71 V8 and an L89 that added aluminum cylinder heads to the 435. These “regular” 427s were also joined by the hard-core L88 with aluminum cylinder heads, cross-drilled, alloy steel forged crankshaft, and a staggering 12.5:1 compression ratio. The L88’s power was underrated by the factory, and it was priced at more than double that of the 435-horse L71, adding about 25% to the bottom line of any Corvette with an owner crazy enough to check its box. A total of 9,723 427-powered Corvettes left the factory in 1967. The L36/390 accounted for 3,832 of those, the L68/400 added another 2,101, and the L71 barely missed out on first place with 3,754 sales. The L89 and L88 were exceedingly rare, with only 16 and 20 produced, respectively. The big power and low production run have been the wind beneath the 1967 L88’s wings on the collector market. The three most expensive Corvettes ever sold at auction were all ’67 L88s, including the $3.85 Million (including fees) all-time record holder.
In spite of an all-new body style, engine options remained the same across the Corvette lineup in 1968 and 1969. Despite this carryover, sales soared. The 390 HP L36 added 7,717 orders to its tally in 1968 and another 10,531 in 1969. The L68 and its 400 horses got 1,932 and 2,072 nods during the first two years of C3 production, and the L71 put another 2,898 notches in its belt for ’68, followed by a final run of 2,722 the year we landed on the moon! After 1967, the word started to get out when it came to the pair of ultra-expensive 427s. In its second year on sale, the $805.75 L89 (vs. the $437.10 of the L71) was installed in 624 Corvettes. Another 390 found new homes in ’69. The L88 was more popular in 1968 by a multiple of four with 80 orders, followed by a relatively astounding 116 takers in 1969 when the RPO’s price had ballooned to $1,032.15. That was a huge sum when you consider the base Corvette’s $4,781 sticker price in 1969, but the 427 had one more trick up its sleeve that would make the L88 look like a bargain. A grand total of 2 L88s were built with a lightweight aluminum block in 1969. This engine wore RPO ZL1, and, at $4,718.35, it all but doubled the price of a Corvette.
The Return: 2006-13 Corvette Z06
The 427 made a triumphant comeback to America’s Sports Car 37 years later in the C6 Z06. This time around, the huge displacement would be applied to modern small-block architecture, creating the definitive example of the breed. Under the moniker LS7, this new beast implemented an aluminum block and heads, an 11.0:1 compression ratio, and a stratospheric 7,000 rpm redline to reach an output that was unthinkable in the 427’s big-block heyday. Peak power of 505 HP arrived at 6,300 rpm, while the plateau of torque reached 470 lb-ft when the engine was spinning 4,800 times per minute. In the first year of availability, 6,272 Z06s were sold. In 2007, that number was up to 8,159, and another 7,731 Zs left Bowling Green in 2008. Amongst the 2008s were 505 Limited Edition models dedicated to the 427, and the plant manager that oversaw all ‘Vette production between 1993 and his retirement in 2008.
A global recession and the hype surrounding its new, supercharged ZR1 sibling knocked Z06 production down to 3,461 in 2009 and just 518 in 2010. A slew of upgrades helped the Z06 outsell the ZR1 904 to 806 in 2011 and 478 to 404 in 2012. The 427’s reign in the Plastic Fantastic ended in 2013 with a final run of 471 Z06s and a 2,552 unit build of 427 Convertibles.
Beyond Production: Racing and Tuners
In 1963, the original Corvette chief engineer, Zora Arkus-Duntov, dreamt of sending his gorgeous second-generation American sports car to compete at Le Mans. His ill-fated C2 racing program included plans to build a minimum of 125 ultra-light high-powered “Grand Sports” for public consumption to appease the homologation gods. As most readers of this site know, General Motors brass pulled the plug on the program after just five examples were complete. Each of the five originally “sported” an aluminum-block 377 cube V8 that made in excess of 550 horses. Before sneaking them out the back door to his racing buddies, Zora ditched the 377s in favor of big-block 427 power. If one of these five legends ever crossed an auction block, you can bet that it would surpass the ’67 L88 as the most expensive Corvette ever sold.
After the factory C5-R program that stormed the competition for 24 poles, 50 podiums, and 31 wins in 55 GT races with an oh, so close 425.9 cubic-inch V8, the C6.R debuted in 2005 with a true 427 hidden under its intimidating yellow body-work. With Zora smiling down on them, C6.Rs won their class at Le Mans in 2005, 2006, 2009, and 2011.
While many tuners have mined the 7.0L displacement for its historical significance and inherent “goodness,” two did it better than anyone else. One of the greatest volleys of the tuning war of the early ‘00s came from Lingenfelter Performance Engineering. LPE’s twin-turbo 427 beast was so fast that the only thing Motor Trend could find to make a fair fight at the strip was a Blue Angels F/A-18 Hornet. With 800 wheel-horsepower and 866 lb-ft going to the rear Mickey Thompson 345s, the Lingenfelter C5 rocketed to 60 in less than 2.0 seconds flat on its way to a blistering 9.24 second quarter at 150.27 mph, making it the fastest car the storied magazine had ever tested. Amazingly, this ‘Vette was able to clear 1,320 feet quicker than the Jet, but from there, the Hornet accelerates to 750 mph in 41 ticks.
When the C7 debuted, and people were most distraught about the re-disappearance of the 427, Corvette Racing engine builder, Katech, stepped up with a cure. For around $30,000, Katech can massage the 2014-19 Corvette Stingray and 2017-19 Grand Sport’s 6.2L LT1 to 7.0 naturally aspirated liters. They don’t just bore out the thing, either. This Street Attack Engine is fully built to the tune of 700 horses. That is Hellcat territory without implementing a supercharger or turbos, just incredible!
Happy 4/27, Corvette Nation! If you are fortunate enough to have 7.0 liters of American fury lurking in your garage, take it out for some celebratory donuts today!
Win a 1966 Corvette Convertible with a 427/390 V8 and Factory Air
[VIDEO] 1969 Corvette 427 vs 1973 Pontiac Firebird in Drag Race
[VIDEO] Watch the Yellow 1967 Corvette L88 Sell for $2.65 Million at Mecum’s Glendale Auction