It's a call that comes just after launch, as the space shuttle clears maximum dynamic pressure, the point where the atmosphere's density and the shuttle's increasing speed coincide. For the moment, the shuttle's Earth-shaking engines are cut back to around 64 percent of their rated power. Then, at around 35,000 feet and at a velocity of over 1,600 mph, the shuttle clears the last obstacle between it and orbit. Across the com crackle those four words, signaling that it's time to drop the hammer and let the rocket fly: "Go at throttle up."

Few get to experience genuine rocket-powered escape velocity. But fewer still get to experience throttle-up in a ground-based rocket putting almost 1,000 horsepower to the ground. For those dedicated few on a quest for ultimate power, willing to pay the price to feel crazy levels of acceleration pushing their eyeballs back in their head and making blood drain from its usual places, the gateway is appropriately called Next Level Performance (NLP) in Altamonte Springs, Florida.

Geoff Skorupa is the guy to see there. Geoff likes building exotic C5 and C6 Corvettes, and he's got a track record of success that caught the eye of Germany's renowned Geigercars, a dealer specializing in U.S. performance cars.

At the SEMA Show in 2007, the rep from Geigercars outlined the goals, the cornerstone of which was a staggering level of horsepower-1,000-virtually double the output of the stock 505hp Z06 engine. And it had to pass German emissions standards. Can you imagine?

But Geoff is the kind of guy who relishes a challenge. The project was on.

Dave Crume, NLP's in-house engine specialist, started with World Products' Warhawk engine block, which features reinforcements in critical areas and provisions for two extra head bolts per cylinder, a key factor in holding up under the extreme compression of twin turbos. The block, costing some $4,500 by itself, was loaded with a super strong Callies forged steel crankshaft, Oliver connecting rods, and coated JE pistons and piston pins with Total Seal stainless steel file-fit rings. Compression ratio was 9.3:1. Piston oilers were installed to help reduce heat load and prevent burning a piston. Coated Clevite bearings gave the rotating assembly maximum durability with minimum friction.

Aluminum cylinder heads, also from World Products, were lightly ported, then fitted with Ferrea stainless steel intake valves and Inconel exhaust valves to live under the turbos' extra heat. Operating the valves is a cam custom ground for NLP, custom Morel lifters, BLP chromoly pushrods, and Jesel shaft-mounted rocker arms. Competition Cams dual valvesprings keep the valves closed when they're supposed to be. Katech custom valve covers and coil relocation brackets were used to top off the cylinder heads.

To feed the beast, a pair of APS in-tank fuel pumps was plumbed with dual stainless steel braided fuel lines, billet fuel rails, 60 lb/hr fuel injectors, and an Aeromotive fuel pressure regulator.

Tucked neatly under the cylinder banks, well out of sight to the casual observer, is a pair of Garrett GT 3582R turbos, part of an APS twin-turbo system with twin air-to-air intercoolers to cool the intake charge before entering the engine. Besides keeping the engine compartment looking tidy and deceptively stock, mounting the turbos near the cylinder banks keeps them right next to the exhaust ports, where hot exhaust gases have all their heat energy to spin the turbine, making throttle response quick and positive. Maximum boost is way up there at 15 pounds.

Post-turbo is a 3-inch stainless steel APS exhaust system specifically tuned for the turbo system. For emissions compliance, NLP added a pair of stainless steel 3-inch catalytic converters.

To keep cool with all the heat and pressure, a pair of DeWitts electric fans works off a 160-degree thermostat.

The balance of the drivetrain had to be proportionally upgraded too. An RPS triple disc carbon clutch assembly transfers the enormous power through an LG Motorsports carbon fiber driveshaft with a solid aluminum rear coupler to an RPM Stage 5 Z06 six-speed manual transmission. Power then flows into a DTE Stage 3 Z06 differential with 3.42:1 gears.

A complete brake package, using Stoptech's huge caliper and rotor combination, slows things down.

Body mods were kept conservative. An LG Motorsports heat extractor hood improves airflow through the engine compartment.

Once the powertrain was assembled, Geoff applied his tuning skills to extract the system's potential. The goal was for the engine to make 1,000 hp. By dialing in the system on NLP's in-house Dyno Jet 224 XLC Load Control dyno, Geoff surpassed that mark, and recorded 914 peak rear wheel hp at just over 6,000 rpm, well beyond 1,000 engine hp when factoring in frictional driveline losses, normally around 18 percent. Check out the dyno sheet. The engine has more than 800 rwhp on tap from about 4,750 rpm on up. And this from a perfectly streetable engine content to idle in traffic with the air conditioner on.

But this Corvette was not built with American roads in mind. It was built to burn up European expressways like Germany's famed high-speed autobahn. You know the problem: You're enjoying some happy throttle time on the European super slab when you come up behind a bottleneck of slow-moving Lambos or Ferraris. What to do? In this high-speed hauler, it's never a problem. This Corvette has hit 219 mph with more to go. So just give 'em a courtesy flash or two of the headlights, then step into as much boost as you have nerve for. You are go at throttle up. Swing into the passing lane and watch the problem disappear in the rearview mirror. Maybe kick the air conditioner up a notch or two. Life is good. Should the slow movers catch up to you at your next exit, it's up to you if you want to pop the hood. You might as well. It'd take a keen eye to spot anything tell-tale. The looks on their faces would be suitable for framing.

Data File: '06 Corvette Z06 Coupe
Owned by: Geigercars, Munchen, Germany
Modified by: Next Level Performance, Altamonte Springs, Florida

Body
Modified production Corvette Z06
Modifications: LG Motorsports Heat extracting hood
Bodywork: Next Level Performance, Altamonte Springs, Florida
Paint: OE Paint

Chassis
Frame: OE C6 Corvette with hydroformed side rails; suspension OE C6 Corvette independent short/long arm with composite leaf spring front and rear
Steering: Production GM rack-and-pinion, power-assisted
Brakes: Stoptech four-wheel discs, slotted rotors
Wheels: OZ Racing 20-spoke alloy
Tires: Pirelli PZero Rassa 285/30 ZR19 front, 345/25 ZR20 rear

Engine
Twin-turbocharged 427
Built by: Dave Crume, Next Level Performance, Altamonte Springs, Florida
Modifications: World Products Warhawk block, Callies forged steel crankshaft, Oliver connecting rods, coated JE pistons and piston pins, Total Seal stainless steel file-fit rings, piston oilers, coated Clevite bearings
Displacement: 427 cubic inches (7.0 L)
Cylinder heads: World Products aluminum, ported
Ignition: Production coil-on-plug
Induction: APS twin-turbo system, 15 lbs. max boost
Exhaust: APS 3-inch stainless steel w/catalytic converters
Horsepower: 914 (measured on chassis dyno)
Torque: 906 lb-ft (measured on chassis dyno)

Transmission
RPM Stage 5 Z06 six-speed manual
Final drive ratio: 3.42:1

Interior
OE '06 Z06 Corvette
Seats: OE '06 Z06 Corvette black leather
Carpets: OE '06 Z06 Corvette nylon cut-pile
Instrumentation: OE Corvette (0-200-mph speedometer, 0-8,000-rpm tach, plus ammeter, oil pressure, oil temperature, coolant temperature, and fuel level gauges) plus fuel pressure/boost gauges on A-pillar
HVAC: OE '06 Corvette

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