Found this at another forum...



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

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:n 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

 

The King of the Hill is back in a BIG way.

 

you are not trisheild

 

just imagine what a pulley swap and tune will get

 

Better be careful - I imagine that this thing is just a bit "closer to the edge" than, say, a '03-'04 Cobra. That's not to say that this is a weak engine or anything, but hell, let's make sure to be respectful of the fact that it's already putting out damn near 640 HP

I'm just curious to see what GM may have done - intentionally or incidentally - to keep people from messing with the tune.

 

If a header swap is as nice to this as it is to a Z06 then 675HP+ isn't far away.

 

Good God.

I was just coming in to start a thread about this.

I think the next Vette is going to need AWD, because we are reaching (or well beyond) the practical limit for how much power can be channeled through two tires! Would be neat to see a next-gen AWD Vette come in at 3500 lbs or less (since the Z06 is just over 3100, and this car is around 3400, I think...). I'm not saying I would choose the AWD car for myself, but when a porker like the GT-R is able to hang with and apparently beat, on some courses, 505 hp Z06...

Or, better yet, keep the 500-600 hp range as tops, but make the next super Vette weigh 2800 lbs.

But back on topic, all hail the LS9!!

 

I personally rather see more effort go into weight savings rather then an AWD system. More Al, Ti and CFRP.

 

Not trying to trivialize the motor at all but why is everyone acting surprised? For the last 6 months I've been hearing that this thing was going to be putting out 650 horsepower... so now it comes in just a hair shy and people are acting surprised in a good way? Were you guys thinking this was just rumors and hype or is it just the excitement of seeing that it's written in stone now?

 

Torque vectoring is likely to extend the limit of 2WD vehicles just a bit.

 

I have officially never heard 650hp. What we've been shown the most was 620-625.

Plus, most people havebeen guessing the torque would be just under 600. 580 and 585 have been put in print

 

whoever said it was going to be 650 hp? maybe a few optimistic guessers...

GM always said 100hp/liter, or 620hp

 

When do we hear about the Ring. Or did the GT-R steal all the thunder?

They should just be confident in their software and make everything read only.

 

A header swap isn't very nice to a Z06. Performance for the dollar ratio sucks. Headers run no less than ~$1500 and over ~$2000 in many cases and the HP/ TQ gains are in the 20-30 range. The factory manifold is already effectively a shorty header and flows very well. A lot of C6 guys are buying Z06 take off exhausts and making big gains.

Can't wait to see ring times for the ZR1. They have to be coming soon.

 

The C7 is supposed to be just that. Same or less power, but smaller and lighter thus more performance.