If you click continue when you get a warning on the link, you will get a nice Excel file breakdown of tech details (stock LS3)... In any event, here's what's in it sans formatting:

2008 "LS3" 6.2L V8 (LS3) Car
41007
Type:
6.2L Gen IV V8 Small Block
Displacement:
6162cc (376.0 ci)
Compression ratio:
10.7:1
Valve configuration:
overhead valves (2 valves per cylinder)
Assembly site:
St. Catharines, Ontario
Valve lifters:
hydraulic roller
Firing order:
1 - 8 - 7 - 2 - 6 - 5 - 4 - 3
Bore x stroke:
103.25 x 92mm
Fuel system:
sequential fuel injection
Fuel type:
premium fuel recommended
Engine Orientation
Longitudinal
Valves per cylinder
2
Bore Center (mm)
111.76
Engine Mass
TBD
Applications:
Horsepower: hp ( kw )
Chevrolet Corvette
430 hp (321kW) @ 5900 rpm SAE CERTIFIED
Chevrolet Corvette w/ Optional Exhaust
436 hp (325kW) @ 5900 rpm SAE CERTIFIED
Applications:
Torque: lb-ft. ( Nm )
Chevrolet Corvette
424 lb-ft (575Nm) @ 4600 rpm SAE CERTIFIED
Chevrolet Corvette w/ Optional Exhaust
428 lb-ft (580Nm) @ 4600 rpm SAE CERTIFIED
Fuel shut off:
6600 rpm
Emissions controls:
catalytic converter

three-way catalyst

positive crankcase ventilation
Materials:

Block:
cast aluminum
Cylinder head:
cast aluminum
Intake manifold:
composite
Exhaust manifold:
cast nodular iron
Main bearing caps:
powder metal
Crankshaft:
cast iron with undercut and rolled fillets
Camshaft:
hollow steel
Connecting rods:
forged powder metal
Additional features:
extended life spark plugs

extended life coolant

oil level sensor

Oil Life System

 

looks like you got some .good stuff in there ,should take a good pounding on the road an track ,

 

Well it's been a while since my last post, the car is still waiting on replacement of a defective box for one of the PLX temp sensors (multiple duds received), then it should be complete.

Tuner's comment was that the car rips on the street. Engine is not broken in so the numbers should rise when the rings seat, and it seems like there is some room for tweaks based on the engine dyno graph when compared. I cannot imagine I should expect a 26% driveline loss in a 4th Gen automatic trans? Would an aftermarket torque arm help this in any way?

Heck the 6th Gen SS w/Auto has only ~10% driveline loss!:
http://www.camaro6.com/forums/showthread.php?t=432140

Rear-wheel dyno:


Engine dyno:

 

looks good the numbers an street all you need ,add twin turbos an get 600hp TO THE WHEELS ,or nitro

 

a lot of the cars making 600 hp just over or under are running twin turbo ,

 

so this is supposed to be 500 at the crank? i would agree you are not getting it yet. i dont see how torque arm would help. may be losing some at converter if its not performing.

 

Yea 574 HP/532 lb ft TQ, I added the engine dyno chart to that post above. I would expect the Yank 3200 stall converter would be a good choice? Wonder what else to try? Cutting out the full airbox opening below? Go from the Stepped 1 3/4 to 1 7/8 headers to all 1 7/8 headers? 4L60E just sucks?

 

what injectors you running. what tb.

 

GM LS3 fuel rails, which TMS says are adequate so long as everything is working optimally.

90mm mechanical 3864 Edelbrock throttle body with mechanical bypass.

 

Your tuner should be able to see if the system is starving for air or fuel. He would have an uncontrollable lean or rich condition. You want to make sure you are running the same fuel as the builder.

Can you get the timing and air/fuel ratio info from the engine builder? Assuming everything is close and you do not have an exhaust restriction then I think looking at the torque converter and transmission would the next step. You need to monitor the engine RPMs and the speed sensor to see if you are maintaining a constant ratio from 4500 RPMs up. If you start seeing RPM increase without speed sensor increase you are slipping. Maybe the tuner can log that info during a pull?

Also have you ever hear the term dyno headers? they are a set of headers that would never fit in anything but a dragster or open hot rod. The headers are designed for one thing. Max numbers at high RPMs They are all but open after the header. If you have a street legal car you can drop 20-30 HP just in exhaust restriction.