C4 Corvette Dressed for the Nines
Car magazines can get you in trouble. Just ask David Stone, a good old boy from Arkansas, who says, “In ‘95, I was reading Hot Rod and they were talking about Vortech Superchargers and how good they’d make a car run. So I had a Vortech put on my ‘92 Corvette. And I liked the way it ran.” The Vortech knocked more than a full second off his 1,000-foot ET (he wasn’t running the quarter-mile then), from a 12.20 to 10.90. But even that wasn’t fast enough for Stone, whose C4 won the title of “Fastest Street Vette In Texas” in 1999. In the process, he went through five engine builds, the last four done by Absolute Performance, a tuner in Jacksonville, Arkansas.
How fast did he have to turn the quarter to win? In ‘99, his 10.81/133 beat all the other Corvettes. But that was after David “slipped past” the safety tech at the Texas Motorplex in Ennis. He’d have won the following fall too, except a hawkeye safety inspector noticed he didn’t have door bars on his roll cage. His consolation was that he did record the fastest ET of the day, a 10.42, and was prepared to hit the high nines with slicks and a full shot of nitrous.
We caught up with Stone at the Viper/Vette Shootout last july at River City Raceway in Marion, Texas, where he ran a best 10.22/140.6 on Mickey Thompson ET street tires. With 580 horsepower to the rear wheels, plus a 175-horse shot of Nitrous Works’ nitrous, Stone was spinning all the way through first gear. His 60-foot times were far short of their potential.
His car is a very serious C4, but it’s entirely street legal. “I drive it to church, and I take my girlfriend out in it. My parents live about an hour and a half away and I drive it to their house. I drive it to Jacksonville, where the tuners are that work on it. That’s 130 miles.”
David is quick to credit Aaron Salisbury and John Simms at Absolute Performance for building his ‘92 LT1/automatic. He met them at the drag strip about a year after he’d installed the supercharger. His car had slowed down, he admitted to Aaron, so AP performed a compression check and discovered the pistons were shot. Superchargers can be tough on stock pistons. The ring lands were broken off and the cylinders were leaking 25 percent, so AP rebuilt the LT1 and installed blower pistons.
David didn’t start off with the killer build he now has. As his enthusiasm grew, he came up with new ideas. Every time, the guys at Absolute Performance got the job done. David remembers the first engine build. “They said I’d probably run high 11s at the most. And the first time at the track I ran an 11.06. So when I saw I could run 11.06, I set my sights on the 10s.”
This final iteration is, as the 580 rear-wheel horsepower screams, on the exotic side. AP replaced the original LT1 block with a 2-bolt version out of a police cruiser. With splayed billet caps, it’s stronger than the 4-bolt LT1. AP also beefed the engine with a Cola crank, Lunati Pro Mod rods, and Lunati blower pistons. Comp Cams ground a special cam – all David will admit is, “It’s a pretty big roller.”
The heads are Air Flow Research, re-worked and fitted with big valves. A big deal are the intake tubes, custom built for AP by race car builder Bobby Shahan of Quick Time Race Cars. Another big change is the switch from speed density, stock on the ‘92, to ‘94 Corvette mass air flow fuel injection.
All the extra power required a stronger automatic, so AP installed a race 400 by TPI, with David also swapping the automatic’s Dana 36 Rear End for a Dana 44 Rear End from a 6-speed Corvette. It’s modified with 3.73 gears (3.42s were stock). The transmission tailshaft is also fitted with a Gear Vendor underdrive unit, which splits the gears so you go from first to first over, second to second over, third to third over. At 60 mph, he’s running 2,300 rpm and gets 21 MPG.
David should have a big surprise for all the folks at Ennis when he shows up to try and whip the Texans. This time, he has a set of those door bars, plus he’s ordered a set of wider Hoosier racing slicks, which have more tread and a softer rubber compound. Obviously, this C4 Corvette is dressed for the nines.