This was an interesting read. That engine was something but to what degree it was a street engine, I don't know. It ran 10.6 seconds at 132 mph on slicks at the time. It had fuel injection. It was a 427 big block.
They also tried other camshaft grinds. Al explained that Chevy’s was “the only grind that will go 7,200 rpm without valve float. At this point we’re getting between 590 and 615 hp (530 to 545 lb-ft. of torque), depending on ram tube length with a modified Lucas/Crower injector. The most significant thing about the engine, though, is that it weighs just 460 pounds ready to go. That’s 40 pounds less than the cast iron 327!”
This is what differentiated it as a Corvette as opposed to a muscle car:The end result: “a complete 550-horsepower ZL-1 427 weighs 20-25 pounds less than a fully assembled 350-horsepower 350!”
Nothing ponderous about any of that.“Sorting the handling of this machine should be as easy as writing in RPO F-41 on the order blank. Standard on all ZL-1’s RPO-F41 means you get heavy-duty disc brakes, increased spring rates, front and rear shocks with improved valving and larger capacity in back, plus a fatter front stabilizer as well as one on the rear. All you add yourself are the serious tires and hope the computers at the GM Tech Center have picked the brain of the right memory bank. With a 43/57 front to rear weight distribution. The 2,808-pound car is almost neutral with just a shade of understeer that you can overpower at will with the throttle. It is the best handling Corvette ever built.”
The ZL-1 option ended up retailing for $6,000—the price of a second ’Vette. Only two were sold to the public, but there was to be a successor …
With normal headers the car’s original dyno sheets indicate 588 hp at 6,400 rpm and 542 lb-ft at 4,800 rpm. Spinning through a little Nova torque converter with a 3,000-rpm stall speed, and running wrinkly-sidewall drag slicks, the car was laying down quarter-mile runs of 10.60 seconds at 132 mph. “Which, against a national class record of 10.75 at 128.75, is impressive. The fact that almost anybody who knows how to drive could jump in and duplicate this run after run may be the most shattering aspect of all.” Alas, Chevy was bleeding red ink in those days and John DeLorean was sent in to fix things up. Part of his solution was to de-proliferate the engine catalog. A planned roster of four Corvette Big Blocks was pruned to one—the 390-hp LS-5 454. It cost $289.65 and found 4,473 takers. It slayed no Ferraris.