When Chevrolet introduced the C6 Corvette there was no denying the positive evolution evident in the chassis and suspension, taking the vehicle to new heights in both performance and comfort. The heralded 400hp LS2 Gen IV engine offers world-class performance and reliability that's hard to beat for the stated power levels. For the enthusiast, a C6 optioned with a Z51 Performance package will give an '04 C5 Z06 a serious run for its money.
Since Corvettes have always attracted a rabid following and are routinely modified to up the ante into the thin air once reserved for supercars, it was no surprise when Motorsport Technologies Inc. of Houston, called and described the following to its wildly successful C5 Z07. It's called a Devil Ray 427.
Beginning with a C6 optioned with the Z51 suspension and handling package, the venerable LS2 gets a healthy dose of stroking and poking and comes out with 427 cubic inches of Gen IV muscle. The heart of the package is the 364ci LS2 and its great new aluminum block. The cast-in liners are removed, and in their place sit a new set of liners that push the bore from 4.00 to 4.125 inches. A forged steel Lunati crankshaft increases the stroke from 3.622 to 4.0 inches. MTI employed hundreds of hours of R&D to develop the package, and at the heart of it are the replacement liners and the proprietary methods employed to achieve the bore. With Lunati pro-billet rods measuring 6.125 inches and Wiseco pistons, the bottom-end is very stout. Topped off with a set of MTI's Stage III-R heads that begin life as stock LS2 units, the end result flows almost 336 cfm on the intake. A relatively mild custom grind MTI "DR1" camshaft measuring in at 228/232 at .050 on .588/.574 lift actuates the valves. MTI tops the engine off with a F.A.S.T. intake, a stock 90mm throttle body, and a beautiful set of custom engine covers with an MTI 427 Devil Ray insignia. The exhaust system gets reworked and features Kooks 1 7/8-inch stainless steel long-tube headers with a 3-inch mid-pipe and high-flow cats. Out back, a Corsa Sport after-cat exhaust measuring 2.5 inches exits from twin 3.5-inch Pro-Series tips.
Upon first glance, the Devil Ray 427 is attractive, but other than the Millennium Yellow color of the car itself, there are no overwhelming visual clues that this is anything but a near stock C6. The polished CCW wheels are sweet as are the tips of the Corsa Sport after-cat exhaust. The car idles very smoothly at around 900 rpm, and the exhaust tone at idle is only slightly elevated over a stocker. Sure, the seats have nice Devil Ray 427 embroidery and a similar decal is on the rear window, but the clues to what lies within are well hidden. According to MTI's owner Jayson Cohen, "Our customer base is interested in having very fast street cars but aren't the types to hit people over the head proclaiming the facts with loud exhausts or an ill-mannered engine combination. We have to create packages that will idle well, be viciously quick, and still be able to pass emissions tests and prove reliable enough to daily drive in congested traffic. The goals of the Devil Ray 427 conversion package was to offer the public an opportunity to have what we perceive to be elevated levels of power over the LS7 based 2006 Z06 at a price that will come in well under the factory offering. Sure, the customer doesn't receive the new aluminum chassis structure or the revised fenders, but we make up for it with raw power. Remember, a C6 optioned with the Z51 Performance package pulls .98 g's, so world-class handling is already at hand. Our Devil Ray 427 engine puts out in excess of 600 crankshaft horsepower and 600 lb-ft of torque. That's right, an even 100hp and 125 lb-ft of torque over the LS7!"
Early on a bright and sunny Houston morning, we headed out to find the perfect place to take photos of the Devil Ray. After driving around for over an hour on all types of terrain, the car rode and drove wonderfully. Jayson was playing it easy because our path was littered with the normal big-city traffic. As we gave up on one side of town and cruised over toward less-inhabited parts, Jayson alerted me to the fact that a yellow dot was starting to appear in the rearview mirror, and had been closing rapidly for the last half mile. As we cruised up to the next red light, luck smiled on us as the yellow dot turned out to be an '04 Lotus twin-turbo Esprit. Weighing a mere 3,000 pounds and carrying 350 much underrated horsepower from it's twin-turbo V-8, we now knew that in the automotive world, a Devil Ray has many predators, especially those carrying $90,000-dollar-and-up price tags and exotic badges. After taking a right onto a divided eight-lane highway, the Lotus snarled up beside us in Second gear. A second later, the owner nodded and mashed the go pedal. After a split second, your intrepid reporter calmly waved goodbye to the Lotus owner and Jayson layed the wood to the C6. Instantly, our wonderfully mannered car woke up and starting growling and spitting F1 rubber. By the time Jayson shifted at 6800 rpm in Second gear, we had the Lotus by two car lengths. As the car accelerated through Third gear and we topped 100 mph, Jayson shut her down with over 10 car lengths separating us from the Esprit. Of course, the Lotus owner didn't take time out to slow down and discuss all things automotive with us at the next light, as his embarrassment at having been beaten like a stepchild was readily evident by the fast right turn that he took. Since this was the first real test of the Devil Ray package since the completion, why ruin the adrenaline rush when there was so much more to wring out of the package? After a quick cruise to an even more remote site, the Devil Ray was run up to 6700 rpm in Fourth gear, cresting the 150-mph mark on the speedometer. One-hundred-fifty mph, and we hadn't even hit the redline in Fourth gear, and had two more gears to pull in. Had the road allowed, we might have exceeded 200 mph before shutting her down. Oh, by the way, a quick toggle of the information center revealed that the coolant temperature was still at 185 degrees. That's right, the cruise around town coolant temp and the 150-mph temp are identical. If you think this isn't a stable engine platform, think again. Before plunking down that deposit on an '06 Z06, give the Devil Ray a look before you too see its taillights receding into the distance!
MTI's C6 Devil Ray 427 PackageThe MTI C6 Devil Ray 427 conversion package is slated for a limited production run of 25 serialized vehicles to ensure their collectability status. The conversion includes complete professional installation and dyno tuning at MTI in Houston. All engine blocks and cylinder heads are sold on an exchange basis. Customers usually arrange for transport to the facility, while MTI is using a fresh 364ci LS2 aluminum block and a new set of GM LS2 heads as the basis for the engine build. MTI will sell the Devil Ray package in a variety of ways, but in order to receive a serial number, the purchaser will need his C6 converted by MTI or arrange to have MTI procure a C6 and perform the conversion. 427ci LS2 engines are sold in a variety of forms with both short- and long-block configurations available. For MTI Devil Ray pricing, conversion scheduling and current numbering, contact MTI at the number listed.
MTI Devil Ray 427 Conversion Package Consists Of The Following*427ci (7.0L) Super-Stroker Engine*MTI Stage 3 Custom Ported And Polished LS2 Heads*MTI Spec "DR1" Custom Camshaft*New LS2 Timing Chain Set And High-Volume Oil Pump*Jesel Shaft-Mounted 1.7 Ratio Roller Rockers*Fast 90mm Intake Manifold And MTI High-Flow Air Intake*Kooks 1 7/8-Inch Stainless Steel Headers, A 3-Inch Mid-Pipe With High-Flow Cats, And A Corsa Sport 2.5-Inch After-Cat Exhaust (Corsa Touring After-Cat Exhaust May Be Substituted By The Customer)*Spec Stage III Clutch With A Billet Steel Flywheel Or Higher-Stall Torque Converter For Automatic-Equipped Cars*MTI Underdrive Crankshaft Pulley Kit*Complete Gasket Set Using Steel Shim Head Gaskets, ARP Head Studs, MTI Hardened Pushrods, And All Necessary Fluids And Filters*Custom-Embroidered Factory Seats And Armrest Featuring "Devil Ray 427" Logo*Custom "Devil Ray" Decals And Badging*MTI Fuel Rail Covers With Custom "MTI Devil Ray 427" Insignia*Custom "Devil Ray" Dash Plaque With An Individual Serial Number*Two-Year/24,000-Mile Limited Engine Warranty*CCW Custom Wheels 18x8.5-Inch Front And 19x10-Inch Rear*Professional Installation And Custom Computer Tuning On A Dynojet Chassis Dyno