This Z06 might look innocent,...
This Z06 might look innocent, but it will destroy nearly anything that lines up next to it—including most supercars.
One thousand horsepower at the wheels—just saying it conveys a feeling of superiority. It's even more menacing when that same Corvette makes that much power and still carries the label of street car. Don't cry foul just yet, because thanks to modern technology, LS-powered Vettes are now capable of cracking the magical 1,000-rwhp barrier, cruising the streets, and gulping down premium pump fuel. If you don't believe us, just call East Coast Supercharging (ECS) in Cream Ridge, New Jersey, and it will be more than happy to prove the point many times over. We got the lowdown on two C6 Z06 rides that were recently completed for a couple of customers who wanted a no-compromise combination that could take on all challengers. ECS tore into the cars and performed what is unofficially known as the Hardcore package.
ECS tuner and front man Doug Ring lays it out simply: "This package will allow you to drive from here to Florida without a problem and still knock down mid-20 mpg." The question we kept asking was, How did we get here? Ring was more than happy to open up the ECS cookbook to show off the Hardcore recipe. Cutting right to it, the combination's fundamentals are simple: a 427ci stroker engine with a great set of cylinder heads, an ECS supercharger system (Vortech YSi-trim head unit), an ample fuel supply, a mild camshaft, and a custom ECS tune.
The engine sounds mild, and...
The engine sounds mild, and even a look under the hood reveals only an ECS supercharger with a Vortech YSi-head unit. The "sleeper" approach doesn't even begin to describe these vehicles.
Getting to this level of performance on the street and track didn't happen overnight. We'd be remiss if we didn't mention the research and development that took place on the company's in-house test mule, a C5 convertible that has seen countless hours on the dyno, thousands of miles on the street, and hundreds of runs down the quarter-mile. The on-track efforts paid off, as Ring and the gang at ECS discovered the right blend of power without sacrificing driveability. This combination is sold as a package because it all works together. Ring chose the RHS LS Race block as the starting point.
The RHS block is molded from A357-T6 aluminum material and is thick in certain areas for strength. The lower end has extra clearance for massive stroker crankshafts, and the tall-deck version is capable of being punched out to a massive 510 ci. Billet main caps ensure the crank doesn't walk around under high loads. A Callies 4.000-inch-stroke steel crank has R&R billet rods and Diamond pistons swinging from it. The bores were opened up to 4.125 inches, bringing final displacement to 427 ci. (The final displacement of V-8 engines is calculated using the formula Bore x Bore x Stroke x 6.2832.)
Making horsepower is about airflow, and ECS turned to Mast Motorsports for a set of its six-bolt LS7 305cc cylinder heads. The heads are stuffed with 2.25-inch intake valves and 1.600-inch exhaust valves. The airflow at 0.600-inch lift is an insane 379 cfm with a 305cc intake port. The exhaust side is just as impressive, as it moves 243 cfm through the port at the same valve lift. Valve angle is listed as 12 degrees.
ECS was more than happy to...
ECS was more than happy to show off the cars' capabilities on its in-house chassis dyno. The black Z06 produced 1,070 rwhp with 19 psi of boost and a cocktail of methanol injection and pump gas.
The ECS camshaft is described as the Bigger Cam, and according to Ring, it's in the mid 230s for duration and under 0.600-inch lift. Its mild nature provides a smooth idle that isn't rough and doesn't cause bucking in the low-rpm range during part-throttle action. The car drives just like any other warmed-over, LS-powered Vette. A stock LS7 intake manifold sits on top of the engine, and air is crammed through a factory throttle body, which, according to Ring, is a big contributor to the car's mild street manners.
Forced induction plays a major roll, and ECS added its in-house supercharger system, which utilizes a Vortech YSi-trim supercharger head unit and front-mounted intercooler. Boost is set at 19 psi, and belt slippage doesn't exist, thanks to the ECS 10-rib-pulley drive system. An ECS/Alky Control Methanol System with two nozzles is utilized, and as Ring puts it, "The meth is basically race fuel on demand."
The system is a progressive setup that is boost-referenced so it only sprays meth when needed. "The meth lowers the IAT [inlet air temperatures] and helps meet fuel demand under high boost, yet allows us to tune the low end on pump gas. It plays a big part in these builds," adds Ring.
An RHS LS Race block was selected...
An RHS LS Race block was selected as the foundation for the 427ci powerplant, due to its A357-T6 aluminum. RHS engineers paid particular attention to the oiling system, and this block has provisions for piston oil squirters and dry sump oiling systems. It also uses a priority main oiling configuration.
The camshaft was kept mild...
The camshaft was kept mild because of the street-going intentions. Ring informed us it was under 0.600-inch in lift, and duration was in the mid-230-degree range. It's referred to as the ECS Bigger Camshaft and may be used in many different LS engine combinations. Comp Cams is responsible for grinding this custom stick.
The Diamond pistons feature...
The Diamond pistons feature flat-tops that are cut to clear the large 2.25-inch intake and 1.60-inch exhaust valves. The compression percolates at a blower-friendly 8.8:1.