Somewhere, around 7,500 rpm in First gear, I fell in love with a C6 Corvette. Driving the car was 20-something shop owner Dan Millen of Livernois Motorsports. I know Dan from his years of heads-up drag-racing battles at some of the country's biggest venues. So, it was a little surreal to be blasting through the streets of Dearborn, Michigan, at three times the posted speed limits, sitting next to one of the first people to run over 200 mph in a street car with 10.5-inch tires. Speed limits be damned! We were out testing Dan's newest bag of tricks-a devilish selection of goodies from the Livernois Motorsports parts bin-a combination that had transformed this 540-mile-old C6 Vette into a whole new car.
Bang! Dan had just stuffed the shifter into Second with the tachometer rocketing toward 8,000 rpm. The independent rear didn't even blink as I got slammed that much farther into the big black seats. Bang! Third gear got popped as mercilessly as the first two, and this new Vette just wanted more. Crushing 100 mph, Dan ecided to back down.
Sitting at a stoplight, he had the politeness to ask, "That's pretty good. Do you want me to try another run?" My approving smile conveyed the answer-I wasn't going to beg. Five or six more trips up the side street like that, and I knew this new Vette was as addictive as any drug. I had to know more about what Dan and his crew had done to it.
Livernois Motorsports is not your average speed shop. Dan and his family have a long history of working with the Big Three automakers, and his resume includes several engineering projects for different subgroups of GM, Ford, and Chrysler. His shop (at least the one building we saw) encompasses 36,000 square feet, with dozens of lifts, a complete engine-and-CNC facility, two chassis dynos, and 35 employees. The building held dozens of project cars, including classic Chevy musclecars awaiting restoration or modification, late-model Mustangs packing 700 rwhp, SUVs that hold a 12-second surprise, and Corvettes.
At an honest 400 horses, the LS2 that comes in your new C6 is one of the most potent production small-blocks to ever roll out of a GM factory. Seriously, this thing will crush most big-blocks from the '60s and leave the vast majority of modern street machines in its wake. Borrowing from the C5 Z06 Corvette, GM installed the high-flowing cylinder heads and deep-breathing camshaft onto a larger displacement (364 cubes), LS-family aluminum small-block to create a real masterpiece of pushrod power. If you've driven a C6 or its not-so-distant cousin, the GTO, then you know what we're talking about.
Dan Millen and his crew looked at this new LS2 as their next test subject. Their in-house engine dyno stayed busy the first few weeks after they got their hands on one (the LS2 is available as a crate engine from GM Performance Parts). They tested several different "stages" of camshaft design, head porting, and electronic tuning to develop different levels of modification to offer their C6 Corvette customer base. They followed that dyno work with installation and evaluation on the evil, black C6 coupe that yours truly got a ride in. Good, solid testing-combined with installation and real-world evaluation in a test car-has allowed Livernois to become a leader in C6 performance. Here's a look at some of the pieces that can help take your C6 to Z06 levels of power.
Cam SelectionHot-rodders have traditionally looked for increased performance by swapping out the camshaft for one that opens the intake and exhaust valves farther off the heads and for a longer amount of time. Livernois took this route with the LS2 engine and struck gold. The stock cam specs out to 204/211 degrees of duration at 0.050 with 0.525 inch of lift and a 116 lobe separation angle. Dan's Stage I camshaft takes those numbers to 218/220 degrees of duration at 0.050 with 0.570 inch of lift and a 114 LSA. This cam boasts an aggressive profile-something the factory can't offer due to various governmental regulations. On the engine dyno, the Stage I cam alone has produced up to 80 hp. In addition-and more importantly-it extends the useable rpm band of the stock LS2 from a respectable 6,000 rpm to a psychotic 7,500 rpm.
HeadsOnce you've promoted deep engine breathing by giving the engine a camshaft that will get the valves working overtime, it's time to look at how to increase airflow through the engine itself. And nothing makes power like a good set of ported cylinder heads. The Livernois Motorsports Stage I CNC-ported cylinder heads feature fully ported intake and exhaust runners, port work in the bowl area, 2.00-inch intake and 1.55-inch exhaust valves, and custom single-coil valvesprings for cams that produce up to 0.580-inch lift. They come fully assembled for $949. Dan recommends his Stage I CNC-ported heads for the typical modified C6 Corvette that sees lots of street action with an occasional blast down the dragstrip or around the road course. The Stage I heads promote good breathing for the small-block LS2 without creating any of the unfavorable characteristics-such as lugging the engine at low rpm-you see with heavily worked heads.
ExhaustWhile the C6 has a good exhaust system, the cam and ported heads point out how restrictive the stock system can be. Dan has worked with Corsa to develop an exhaust system that "screams when you want it to and whispers when cruising." This system is constructed of stainless steel and is completely emissions legal. Nothing deflates the value of your Corvette like a cheap exhaust system that has a lot of drone or is so loud your date has to yell at you while you're driving. Millen's test car was equipped with the Corsa Touring exhaust system with twin 3.5-inch Pro-Series tips. The test car still runs the stock exhaust manifolds and mid-pipes. These items can be replaced for even more power (see sidebar), but Dan liked the quiet and deceptive nature of the car with a mild exhaust.
ConclusionLivernois rounded out the C6 Vette with a lowering job and a set of HRE 545R wheels (19x9.5 front, 20x11 rear). Dan himself handled all of the custom engine tuning, and the end results were an impressive 409 rwhp and 373 lb-ft of rwtq. But you get so much more with this combination than just a "box of parts." As stated earlier, Dan spent a lot of time testing different parts and combinations in the car, both on the chassis dyno and on the road. Combining big rpm potential with the supporting pieces to make it all work seamlessly, the Livernois crew is really onto something. We think you'll agree.
To The ExtremeWhile we were visiting the Livernois Motorsport facility, Millen showed us another C6 his crew was just finishing for one of his customers. This car took Dan's street C6 a little bit further with a set of the Stage I heads, a Stage II cam (with even more lift and duration), Kooks long-tube headers and X-pipe, a Corsa after-cat system, a Halltech Stinger cold-air intake, and a custom tune by Livernois. With just 2,500 miles on the clock, this silver C6 banged out 445.5 rwhp and 402.1 lb-ft of rwtq. This gives you an idea of how much the stock intake and exhaust manifolds are holding back the black coupe-roughly 35 rwhp and 30 lb-ft of rwtq. It also shows you how quickly these LS2 engines become really serious. While we were at Dan's shop, a stock '06 Z06 spun the chassis dyno to 450 rwhp. For a little time in the shop, you could have a real animal on your hands with the base C6.