ZRCLONE

Anyone know where to get specs on this LS3 engine 480 HP, #19244549? Is the only difference between the LS3 in the Vette LS3@430 HP the GM Hot Cam #88958733. Seems like the same exact specs other than the cam. 50 HP with just this GM cam, or are there any other differences, valve springs etc. Thanks for any help.

LS1LT1

LS 376/480HP

475 Ft. Lbs @ 4,500

The hot new small block V8 in the GM lineup is the hyper-aggressive LS3. It offers a high-revving 376-inch combination that represents generations of small block V8 development and engineering. Not only is the LS3 an amazing engine in its stock configuration, but with those high-flowing rectangular port cylinder heads, the LS3 is loaded with potential. To tap into this potential, the engineers at GM Performance Parts offer you the LS 376/480 - an LS3 with an upgraded camshaft that ups power by a whopping 50 horsepower!

The LS 376/480 comes with the same great features as the LS3 crate engine. The bottom end includes a 6-bolt aluminum block, nodular crank, high performance rods, and 10.7:1 pistons. The heads are high-flowing rectangular-port units that share their design with the amazing LS7. The same EFI intake manifold feeds the hungry engine, while 1.7:1 roller rockers work with the upgraded camshaft.

The GM Performance Parts engineers picked the LS Hot Cam (p/n 12617570) to take the LS3 to the next level. This cam specs out with .525-inch intake and exhaust valve lift. Duration (@ .050 inches) is 219 intake and 228 exhaust. This cam allows for a dramatic increase in power across the power band while still maintaining good street manners. The engine will idle and cruise just like an LS3, but the power increase is there whenever you need it.

With all of the same great components as the LS3, but with an additional 50 horsepower, the new LS 376/480 is ready, willing, and able to answer your call for a new LS crate engine.

Specifications:
Power: 480 HP @ 5750 RPM, 475 ft. lbs. of torque @ 4500 RPM
Displacement: 376 CID, 6.2L
Bore x Stroke: 4.060” x 3.620”
Compression Ratio: 10.7:1
Recommended Fuel: 92 Octane
Block: Cast Aluminum with 6 bolt cross bolted main caps.
Crankshaft: Nodular Iron
Connecting Rods: Powdered Metal Steel
Pistons: Hypereutectic Aluminum
Camshaft: Steel Hydraulic Roller Tappet
Cam Lift: .525” Intake / .525” exhaust
Cam Duration @ .050”: 219 deg. Intake / 228 deg. Exhaust
Lobe Separation: 112 Degree
Cylinder Heads: Aluminum L92 style ports.
Combustion Chamber: 68cc
Valves: 2.165” Intake/ 1.590” Exhaust
Rocker Arms: Cast Roller Trunnion, 1.7:1 Ratio
Balance: Internal
Reluctor: 58X
Maximum GM Recommended RPM: 6600

Engine Includes:
• Fully GM assembled long block
• Ignition Coils, Plug Wires and Spark Plugs
• Oil pump, pick-up and Corvette oil pan
• Exhaust Manifolds
• Intake, Injectors and Throttle Body
• 14” Auto Trans Flexplate
• Harmonic Balancer
• Front timing cover
• Aluminum Water Pump
• Oil Filter
• Passenger Side RH Oil Dipstick and Tube

Warranty:
General Motors limited 2 year / 50,000 mile parts & labor warranty.

ZRCLONE

With all of the same great components as the LS3, but with an additional 50 horsepower, the new LS 376/480 is ready, willing, and able to answer your call for a new LS crate engine.

Thank you sir.
I have seen this and also the same for the LS3 430HP. They appear to be identical except for the cam.

I am trying to find out the smaller details of any other differences.
Is the extra 50 HP with the cam swap only? Is the rest of the valve train identical? Valve springs, lifters and are the rockers "full roller"?
Thanks again

glass slipper

The extra 50 HP does not all come from the cam. The LS 376/480 uses dyno headers/exhaust with no cats/mufflers. With only .525" lift, there is no reason to change the valve train especially since the extra duration actually makes it easier on the springs. The 112 degree LSA means torque isn't lost down low as the DCR isn't affected but peak HP comes on sooner as the 5750 RPM peak shows...you may have just a little bit of "chop" at idle too. I'm not sure but I seem to remember the 480 HP rating is STD vs SAE for the 430 HP rating...STD gives you ~4.5% higher ratings. I'll have to do some more digging on that one.

ZRCLONE

Thanks much for the response!
According to the crate engine specs side by side on GM sites they are identical with the exception of the GM Hot Cam. Right down to the cast iron exhaust manifolds, intake and TB.
I already have Headers with High Flow Cats, NPP Exhaust and a Vararam.