Posted on 04/25/2008 7:24:46 AM PDT by Red Badger
When Chevrolet officially announced the new Corvette ZR1 just before the Detroit Auto Show this year, it hadn't yet finished the certification of its new power-plant, the supercharged LS9. At that time, all the engineers would tell us was that the supercharged 6.2L V8 would produce a minimum of 100hp/L or 620 hp. Three months have passed since we got our first official look at the LS9 and the numbers are now in. According to GM, the LS9 has now been SAE Certified at 638 hp and 604 lb-ft of twist. The official EPA fuel economy testing hasn't been finished and for people who buy a ZR1 it probably won't matter anyway. Nonetheless, GM expects the LS9 to be the most fuel efficient 600+hp engine in the world, a dubious distinction if ever there was one. A special team of technicians will be hand-building and testing the LS9 at GM's Performance Build Center in Wixom, Mich. Check out the articles below for all the details on the ZR1 and LS9.
CHEVROLET ANNOUCES CERTIFIED POWER RATINGS FOR THE NEW CHEVROLET CORVETTE ZR1: 638 HP FROM THE SUPERCHARGED LS9 V-8
PONTIAC, Mich. – When it was introduced at the North American International Auto Show in Detroit earlier this year, the 2009 Chevrolet Corvette ZR1's power was estimated at 100 horsepower for each of its 6.2 liters of displacement. GM Powertrain has completed SAE certification of the ZR1's supercharged LS9 V-8 and the results exceed the estimate: 638 horsepower (476 kW) and 604 lb.-ft. of torque (819 Nm).
The LS9's output is nearly 103 horses per liter, or just about 1.7 horses for each of the engine's 376 cubic inches. It is unquestionably the most powerful automotive production engine ever manufactured by General Motors and enables the Corvette ZR1 to achieve a top speed of more than 200 mph (322 km/h).
"One of the most amazing things about the Corvette ZR1 is the level of refinement that our designers and engineers have attained. Even with all that power, this car has road manners that will allow our customers to enjoy it on the streets as a daily driver, and on the track," said Chevrolet General Manager Ed Peper.
The Corvette ZR1 goes on sale this summer. Its 638-hp supercharged engine is complemented in the chassis by heavy-duty components not offered in any other model, including a six-speed manual transmission with race-hardened gears and dual-disc clutch technology that delivers exceptional clamping power and lower inertia, as well as strengthened axle components.
Fuel economy testing has not been completed, but engineers are confident the ZR1 will be the most fuel-efficient 600-plus-horsepower car on the market.
The LS9 engine is hand-built by specially trained technicians at GM's Performance Build Center in Wixom, Mich. It is a unique, small-volume engine production facility that also builds the Chevrolet Corvette Z06's LS7 engine and other high-performance GM production engines.
"Developing the LS9 involved more than simply striving for a great horsepower number. Endurance and reliability testing have shown the engine to be robust and low-maintenance, just like other engines in the small-block family," said Sam Winegarden, executive director, engine engineering for GM Powertrain. "That it is distinguished as the most powerful engine ever from General Motors is a source of immense pride among everyone involved with the LS9."
Supercharged aspiration The key enabler of the LS9's performance is the industry's first production application of a new, positive-displacement Roots-type supercharger that has a unique four-lobe rotor design. Its design promotes quieter and more efficient performance, while the large, 2.3-liter displacement ensures adequate air volume at high rpm. Maximum boost pressure is 10.5 psi (0.72 bar). It is teamed with an integrated charge cooling system that reduces inlet air temperature for maximum performance.
"The combination of large displacement and the new, four-rotor design broadens the effective range of the supercharger, allowing the engine to make more power at lower rpm and sustain it throughout the power band," said Winegarden. "The low-end torque is tremendous and the high-rpm charge from the supercharger is simply amazing."
A raised hood provides adequate clearance for the LS9, while a polycarbonate window in the hood provides a view of the engine beneath it.
LS9 details The LS9 features many unique design and manufacturing details that support its high-performance nature. They include: Aluminum cylinder block with iron cylinder liners that are finish-bored and honed with a deck plate installed Forged steel crankshaft with a nine-bolt flange Titanium connecting rods and forged aluminum pistons Stronger, rotocast cylinder heads with 2.16-inch (55 mm) titanium intake valves and 1.59-inch (40.4 mm) hollow-stem, sodium-filled exhaust valves Camshaft with 0.555-inch (14.1 mm) lift for excellent idle and low-speed driving qualities A dry-sump oiling system with 10.5-quart (9.9 liters) capacity Integrated oil cooler and piston-cooling oil squirters Intercooler cover visible through the hood window that features ZR1-unique blue accents and "LS9 SUPERCHARGED" embossed on the left and right sides
Specifications
LS9 6.2L SUPERCHARGED V-8 Displacement (cu in / cc): 376 / 6162 Bore & stroke (in / mm): 4.06 x 3.62 / 103.25 x 92 Block material: cast aluminum Cylinder head material: A356-T6 rotocast aluminum Valvetrain: overhead valve, 2 valves per cylinder Fuel delivery: SFI (sequential fuel injection) Compression ratio: 9.1:1 Horsepower / kW: 638 / 476 @ 6500 rpm Torque (lb-ft / Nm): 604 / 819 @ 3800 rpm Fuel shut-off (rpm): 6600 Recommended fuel: premium required Exhaust manifolds: stainless steel Main bearing caps: forged steel Crankshaft: forged steel Camshaft: hollow steel; 0.555-in (14.1 mm) lift Connecting rods: forged titanium Valves: intake: titanium exhaust: hollow steel Valve lifters: hydraulic roller Supercharger: R2300, four-lobe "Roots" type (2.3L) Additional features: piston oil-spray cooling; direct-mount ignition coils; 11-rib accessory drive
But will it run on 10% ethanol or is it high octane only?
I will be anxious to see those documented results.
I just laughed at the bragging of being the best of the worst.
I think it is a great machine and I wished I had one.
Cheers.
I don't know about your town, but going through my town at 175 mph is not that useful.
The only alcohol in this car will be in the windshield washer reservoir........
But between towns in West Texas and Montana...
Wrong. The first production OHV engine was the Oldsmobile Rocket V-8 in 1949.
The older design is OHC. Even DOHC predates OHV by a couple of decades. Pushrod is actually the more modern design.
That said, each design has its advantages and disadvantages. Pushrod engines are smaller for their displacement, but can't rev as high. OHC engines have the timing belt/chain issue.
That caught my eye, too. Can you imagine what this little hummer would produce if the heads/valve arrangement were state of the art; i.e., twin OHC, 4 valves per cylinder etc.?
800 horsepower production car. I want one.
I think you’re confusing valves and cams, maybe?
Another "Blast From The Past"---Duntov,,,,,Isky?
You teach product knowledge for Chevy through out our southwest, yet spell this car’s abbreviated name, “Vet”? And as to its being the most fuel-efficient 600 hp car, my Asian daughter was recently awarded as the Student of Color with Highest Grade Point Average at her small, rural, northeastern, public college. “Yay”, she exulted, “I’m the highest scoring white guy on a basketball team!”
The new Nissan GT-R is ten times hotter and anyway who wants a $70,000 plastic car.
OHV simply means the valves are on top. The means by which the valves are opened can be either Overhead cam (no pushrods) or in block cam via push rods.......
What would have been cool would be to use the ZL1 motor. Double overhead cams and 4 valves per cylinder. I think it was built by Mercury Marine?????
It doesn’t have overhead cams. But I’d take one anyway.
You are correct; the early Alfa Romeo engines from the '30's, designed by Enzo Ferarri, were DOHC designs. I think Alfa still builds that engine; I had a 1974 GTV coupe that was one of the sweetest cars I've ever owned.
The GTR is very cool. R&T tested it, the Porsche 911 Turbo and the Z06 Vette and beat both of them.
the non turbo zo6 505 hp is posted at 21/27 in stick
actual numbers are plus 1 and plus 1
and she msrp’s at 72.5 in total full dress
that would look really nice
...in something besides a corvette
did you have a point for just extra time on your hands ?
It would really look nice........in my car.......
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