With factory performance levels continuing to chart an upward trajectory into the troposphere, it's increasingly difficult to build a speed-modded Corvette capable of reliably slackening jaws at the weekly club night or cruise-in. But while opinions may vary slightly as to what constitutes the "new normal" among the horsepower elite, a figure of 1,000 ponies seldom fails to elicit the desired outbreak of hushed awe and wholesale gawping.
Dave Cell took a significant step toward dyno-sheet superstardom early last year when he installed one of ProCharger's new P-1SC blower kits on his Atomic Orange '09 Z06, a process we covered in detail in our July '10 issue ("Air to the Throne"). Thus fortified, the car cooked up a rousing 583 horses and 512 lb-ft of torque at the rear wheels, handily outpointing its uplevel sibling, the ZR1, in both measures.
For most Corvette enthusiasts, that would have been a logical stopping point, but Cell—a former GM powertrain engineer—soon found himself dreaming up ever more outrageous forced-induction engine combinations for his daily driven Z. When his febrile imaginings finally coalesced around a supercharged, 1,000hp mill capable of withstanding the rigors of top-speed, standing-mile, and open-road racing, Cell set about compiling a list of hardware upgrades needed to make that dream a reality.
The first piece to come in for scrutiny was the blower itself. While the P-1SC head unit already installed on the car was ideally suited to its intended mission—namely, inflating the output of street/strip cars equipped with stock or lightly modified engines—it was never intended to support the Can-Am–quality power levels Cell hoped to achieve with his new combo. ProCharger's Jeff Lacina recommended a step up to the company's F-1A supercharger, a larger, race-oriented unit that also happened to be compatible with Cell's existing bracketry. An eight-rib drive—to keep the belts wrapped tightly at high rpm—completed the simple-but-effective blower upgrade.
Equipped with ProCharger’s...
Equipped with ProCharger’s off-the-shelf LS7 blower kit and “generic” ECM tune, Dave Cell’s ’09 Z06 cooked up a ZR1- toppling 583 hp and 512 lb-ft of torque at the rear wheels during testing early last year.
Next up was the engine itself. For all its putative "race-inspired engineering," the LS7—with its frangible rod configuration and high-compression cast pistons—makes a singularly poor forced-induction motor when high boost levels are required. Since Cell's recipe called for up to 16 psi of puff from the new ProCharger setup, a replacement mill was clearly in order.
After weighing his options, Cell settled on an iron LSX cylinder block from GM Performance Parts to undergird his new combination. Topped with ported GMPP LSX-LS7 heads and assembled by Fast Forward Racing Engines in Zephyrhills, Florida, the bombproof LSX casing should prove more than capable of withstanding the sustained full-throttle torture sessions to which Cell is sure to subject it.
There were, of course, innumerable other upgrades and fortifications required to support the new combo, most of which we've attempted to address in the accompanying photos and buildsheet. As you'll see, wringing 1,000 hp out of a reliable, street-worthy package requires a patient, holistic approach to engineering that is quite at odds with the zeitgeist of instant gratification promoted in many Internet forums and, yes, magazine articles. No, the new normal doesn't yield itself readily to quick fixes, but for those willing to follow a meticulously conceived build plan like the one outlined here, the payoff should prove well worth the wait.
While ProCharger doesn’t offer...
While ProCharger doesn’t offer a complete F-1A kit for the Corvette, the larger unit bolts right up to the existing brackets, making it the ideal incremental upgrade.
The prime mover in Cell’s...
The prime mover in Cell’s new engine package is this F-1A supercharger head unit, capable of moving 1,650 cfm of air and supporting 1,100 hp (as compared with 1,200 cfm and 825 horses for the standard-issue P-1SC).
ProCharger also contributed...
ProCharger also contributed this racing blow-off valve, which was attached to a custom mount fabricated by Greg Lovell at AntiVenom. In addition to making those cool whooshing sounds you heard in the Fast and Furious movies, a BOV vents compressed air to keep the blower spinning during upshifts and other closed-throttle situations.
The coffee-table-sized intercooler...
The coffee-table-sized intercooler from the original supercharger kit was adjudged sufficiently capable and reused.
Since the new setup called...
Since the new setup called for as much as 16 psi of boost, Cell wisely upgraded from the stock LS7 aluminum block to this GM Performance Parts LSX iron unit. The LSX’s heavy-duty construction and two additional head bolts per side make it perfect for use in a high-boost combination such as this one. Displacement remains a Z06-appropriate 427 ci.
Topping the new block are...
Topping the new block are a pair of LSX-LS7 heads from West Coast Cylinder Heads. With the company’s Stage II CNC porting, these heads yield a final compression ratio of 9.8:1 and handily outflow the excellent LS7 stockers.
A peek down the exhaust port...
A peek down the exhaust port offers a good look at the lapidary quality of the WCCH porting. The company also opened up the combustion chambers to 73 cc’s to help unshroud the valves.
When it comes to forced induction,...
When it comes to forced induction, what goes in must come out. These 1 7⁄8-inch long-tube headers from American Racing Headers should prove more than equal to the task.
The ARH headers feature stainless...
The ARH headers feature stainless steel construction and come with both high-flow catalytic converters and an X-style crossover pipe.
Lovell modified them to accept...
Lovell modified them to accept sensors for monitoring the engine’s air/fuel ratio and exhaust-gas temperatures.
Although the ProCharger intercooler...
Although the ProCharger intercooler is perfectly adequate for street and drag-racing applications, Cell decided to backstop it with this water/methanol-injection kit for use in top-speed and open-road competition.
The meth kit displaced the...
The meth kit displaced the stock windshield-washer-fluid reservoir, a trade-off Cell was happy to make. Lovell plumbed the system with custom hard lines and installed a drain plug to facilitate quick fluid change-outs.
Underneath, Cell replaced...
Underneath, Cell replaced the factory Z06 driveshaft (bottom) with a burly 3.5-inch aluminum unit from the Driveshaft Shop. The DS piece is said to be good for 1,000 rwhp, and, unlike a pricier carbon-fiber piece, it should prove virtually invulnerable to damage from road debris. Polyurethane couplers are significantly tougher than the stock rubber “donuts.”
Axle failures aren’t terribly...
Axle failures aren’t terribly uncommon on enthusiastically driven C6s, and upping engine output only exacerbates the problem. Cell dumped the stock axles in favor of Driveshaft Shop “1,000hp” units, mating them to the stock (!) Z06 rearend. “Fingers crossed,” he says of the unorthodox pairing.
The factory clutch is another...
The factory clutch is another weak spot on enhanced-output Z06s, so Cell replaced his with a triple-disc carbon setup from RPS. An SFI-approved bellhousing (installed after this photo was taken) should be considered mandatory on any car making this level of power.
The stock brake rotors on...
The stock brake rotors on Cell’s car were showing small cracks around the drill holes, so he ordered up a fresh, fissure-free set. Carbotech pads, Doug Rippie stainless lines, and a Quantum Motorsports cooling kit buttress what is already a superb braking system.
More power—especially more...
More power—especially more supercharged power—almost always means more heat, and in a small engine compartment such the C6’s, that can be a real problem. A DeWitt’s aluminum radiator loaded with distilled water, Red Line Water Wetter, and a gallon of DexCool (for water-pump lubrication) should help the blown Z keep its cool.
Cell kept the factory Z06...
Cell kept the factory Z06 exhaust system but sprayed it Ferrari-style flat black to match the stripe on the car. Lovell also modified the mufflers internally for increased flow, and installed a “Mild 2 Wild” switch to bypass the sound deadening altogether. With the switch activated, the Vette sounds like a Cup car prowling the paddock at Daytona.
Final engine assembly was...
Final engine assembly was handled by Joe Irwin at Fast Forward Racing Engines, after which Lovell shoehorned the big stroker into the car. Note that the headers were ceramic coated prior to installation, the better to keep engine-bay temps to a minimum.
Cell plans two different boost...
Cell plans two different boost configurations for the new engine combo. The first will employ a 4.75-inch blower pulley and water injection to generate around 10 psi and a target output of 725 rwhp. The second will rely on a 3.7-inch pulley and methanol injection to pump out 15 to 16 psi and generate approximately 925 rwhp. We’ll be back with the final test results in an upcoming issue. vette
ProCharged LSX Z06 Buildsheet
Second-generation LSX block; bored to 4.125-in, decked, and line-honed
Callies Dragonslayer crank; 4-in stroke, LS7 configuration
Oliver Speedway 6.125-in rods
Diamond custom forged dished pistons, 9.8:1 final compression
Diamond tool-steel piston pins
Steel-top ring set
Calico coated main and rod bearings
ARP main studs
ARP "6-bolt" head studs
GM LSX 6-bolt steel head gaskets, 0.041-in
Stock LS7 oiling system
ATI eight-rib Super Damper, 7.53-in
GM LSX-LS7 cylinder heads
Stage II porting by Richard Reyman/West Coast Cylinder Heads
Combustion chambers opened up to 73 cc's to unshroud valves
Del West titanium intake valves, stock size
REV stainless exhaust valves, stock size
PRC EHT valvesprings
Comp Cams custom grind (0.630-in lift, 232/256-deg duration, 114-deg LSA, 110 ICL)
Morel link-bar lifters, 0.750-in rollers
Trend custom 3/8-in pushrods, 0.080-in wall
Cloyes Extreme HexAdjust timing set
Stock LS7 rockers, converted to bushed bearings by CHE
LS7 intake manifold, ported by Pete Incaudo/VMax Motorsports
LS7 throttle body, ported by Pete Incaudo/VMax Motorsports
Katech valve covers and coil mounts
MSD ignition wires
CoolTech plug-wire shields
NGK BR7EF plugs
All engine work by Joe Irwin/Fast Forward Racing Engines
ProCharger F-1A with eight-rib drive
ProCharger intercooler from standard Z06 kit
ProCharger racing blow-off valve with custom mount by Greg Lovell/AntiVenom
"Big Mouth" air filter and ducting from Taylor Sims/Dallas Performance
Intake-manifold inlet tube from Taylor Sims/Dallas Performance
4.75-in pulley for "street" tune, 3.7-in pulley for "race" tune
ProCharged LSX Z06 Buildsheet (Continued)
American Racing 1 7/8-in headers, ceramic-coated and modified for wideband/thermocouple installations
American Racing high-flow cats and X-crossover pipe
Stock LS7 exhaust with "muffler mod" by Greg Lovell/AntiVenom
Mild 2 Wild exhaust switch
Modified Dallas Performance "1,800hp" fuel system with custom hard lines by Greg Lovell/AntiVenom
Fuelab 515 boost-referenced fuel-pressure regulator
Siemens 80-lb/hr fuel injectors
Dallas Performance fuel rails
AlkyControl methanol-injection kit with custom drain line and valve by Greg Lovell/AntiVenom
Dallas Performance frame mount for methanol pump
Dual Dallas Performance stainless steel methanol-injection nozzles
RPS BC3 billet triple-disc carbon clutch, steel flywheel
RPS slave cylinder
QuickTime SFI-approved bellhousing
The Driveshaft Shop "1,000hp" 3.5-in custom heavy-duty aluminum driveshaft
The Driveshaft Shop 12mm polyurethane driveshaft couplers
Stock Z06 transmission/rearend
The Driveshaft Shop "1,000hp" Level 5 axles
East Coast Supercharging halfshaft safety loops
Stock Z06 brakes with Carbotech 1521 one-piece pads
Quantum Motorsports spindle ducts and cooling kit
Doug Rippie Motorsports stainless steel lines
Motul 660 fluid
Pfadt Sport Shocks
AEM wideband, connected to an HPTuners MPVI for datalogging and tuning
SPA Technique dual fuel-pressure/boost gauge
SPA Technique dual EGT gauge
Autometer A-pillar gauge mount
Mounting and custom reset buttons by Greg Lovell/AntiVenom
Custom catch can by Taylor Sims/Dallas Performance
Catch can/PVC plumbing by Greg Lovell/AntiVenom
DeWitts A05A aluminum radiator, modified by Taylor Sims/Dallas Performance for oil-cooler-line clearance
Liberal use of CoolTech heat insulation products where advisable