525 hp LS3

[OldScoolCamaro]

Originally Posted by Q-ship

You know that the LS3 and the L92 are basicly the same head when it comes to flow? The only difference in the GMPP catalog is that the LS3 has a slight advantage in the amount of lift it can take.

LS3 max lift (as machined from GM) is .570
L92 max lift (as machined from GM) is .510

...looks to me that the only difference between them are the valve springs and hollow versus solid stem intake valves, otherwise they are the identical head. Heres some specs from GMPP...and look at the flow at .600" lift!!!!

"

12629051

Bare L92 Aluminum 260 15 deg 70 2.165 1.590 L92 Std LS Bolt-down Bare L92 N/S

12629064

Stock L92 Aluminum 260 15 deg 70 2.165 1.590 L92 Std LS Bolt-down Solid stem valves 229

12629063

Stock LS3 Aluminum 260 15 deg 68.4 2.165 1.590 L92 Std LS Bolt-down Hollow/solid 229

12629051

Bare LS3 Aluminum 260 15 deg 70 2.165 1.590 L92 Std LS Bolt-down Bare LS3 N/S"

and......

"12629064

L92 Cylinder Head Assembly (not shown)

• Aluminum performance head

• Fits any LS family engine with 4.000" bore or larger

• 2.165" solid stem intake, and 1.590" solid stem exhaust valves

• .510" max valve lift

• As-cast L92 style intake ports

• D-shaped exhaust ports

• As-cast combustion chambers

Head P/N 12629064 is assembled with the following components:

12627970

Intake Valves 10166344 Valve Spring Retainers
12582719

Exhaust Valves 12482063 Intake Valve Stem Seals
12589774

Valve Springs 12482062 Exhaust Valve Stem Seals

10166345

Valve Locks

L92 Head Flow Data (4.000" Bore):

Lift

0.200" 0.300" 0.400" 0.500" 0.600"

Intake

151 208 256 294 316

Exhaust 111 152 174 183 189

12629063

LS3 Cylinder Head Assembly (not shown)

• Aluminum performance head

• Fits any LS family engine with 4.000" bore or larger

• 2.165" hollow stem intake, and 1.590" solid stem exhaust valves

• .550" max valve lift

• As-cast L92 style intake ports

• D-shaped exhaust ports

• As-cast combustion chambers

• Uses bare head

P/N 12629051"

Heads 12629063 and 88958758 are assembled with the

following components:

12569427

Intake Valves 10166344 Valve Spring Retainers

12582719

Exhaust Valves 12482063 Intake Valve Stem Seals

12625033 Valve Springs 12482062 Exhaust Valve Stem Seals

other technical tidbits on intake vales......

"One way valve suppliers are taking additional weight out of intake (and exhaust) valves today is offering "hollow stem" valves. The valve stem is gun-drilled and micropolished to make it hollow like a pushrod. The drilling is only done in the upper 2/3 of the stem where rigidity is less of a factor than the area just above the valve head. After the stem has been drilled out, a hardened tip is welded onto the top of the stem. The result is a valve that is 20 to 22 percent lighter than a valve with a solid stem.

According to one supplier of hollow stem performance valves, the valves are good for 300 to 350 more rpm with no other modifications (same springs, rockers, pushrods, etc.).

Drilling out the valve stem to lighten the valve obviously sacrifices some strength, so a slightly stronger valve alloy may be used to maintain the same strength as before. One supplier of hollow stem performance valves said the durability of hollow stem valves is not an issue in naturally aspirated performance engines. But he did not recommend using hollow stem valves in turbocharged or supercharged engines, or in engines using nitrous oxide because of the increased heat."

....hollow intake valves and bigger springs allow the higher lift camshaft profile..... and account for the recommended cam lift specifications as listed. The L92 head design is a winner. It can handle .600" intake lift easily, providing there are no piston to valve issues.

...heres more great valve information if you would like to brush up on technical details.......

http://www.enginebuildermag.com/Article/1285/performance_valves.aspx

[OldScoolCamaro]

Originally Posted by knitetrain05

They where made due to the cost of fuel and to give a car to the rice burners. Not a true muscle car. Pony car yes,muscle car no. SS, ZL1 Are muscle cars

The L92 head design is the staple of the mighty LS family (except for the LS7 which is taken to another level). It's a marvelous design with alot of high tech engineering placed into it. It flows like the wind. It's amazing what characteristics they put into this casting. It's truely factory high performance. For starters, read about it here.....some great insight and technical information is listed...

http://www.camarohomepage.com/ls3/index.htm

[Camaroshark]

Originally Posted by shank0668

http://gmauthority.com/blog/2011/11/...ower-in-a-box/
Could have potential for a track car.

Could have potential for street cars.

[Setnom]

Hi,
Where I can find a program to the ECU for this engine?

[WHAMMO]

The 226/236 110lsa seems like a very potent grind. And with 525lift, its pretty easy on the valvetrain. Some similar grind, with higher lift, have put 450rwhp already.

[Snidely Whiplash]

Originally Posted by b4z

With that lift and the only 110 LSA it's gonna have a lot of lope. Probably more than a lot of people would like.

Duration, lobe profile, and lobe separation have an effect on idle quality of any given camshaft. The camshaft lift has nothing at all to do with idle "lope".

[Snidely Whiplash]

Originally Posted by Q-ship

You know that the LS3 and the L92 are basicly the same head when it comes to flow? The only difference in the GMPP catalog is that the LS3 has a slight advantage in the amount of lift it can take.

LS3 max lift (as machined from GM) is .570
L92 max lift (as machined from GM) is .510

Of the hundred or so small block Chevy motors I built for myself and friends back in the day, I never found heads to be a limiting factor of valvespring lift. The limiting factor is the valvesprings having the ability to handle the lift and not bind (and valve to piston clearance - but the pistons are easily flycut). If you needed bigger springs to obtain proper seat pressure required by the camshaft, you merely had the spring seats machined.

[The_Blur]

This is really exciting, but let's not start jumping engines. We already have LS3/L99 engines. We can get that cam, but I'm very confident we won't have 525 ponies at the crank.

For those of us modding our cars, this is GM reassuring us that valve springs and a cam make good, reliable power in the LS3/L99.

[ShnOmac]

This kind of reminds of the "Friday" thread..... It just won't die.

[The_Blur]

Originally Posted by ShnOmac

This kind of reminds of the "Friday" thread..... It just won't die.

With PRI and SEMA, this totally fooled me. I should've looked at the date.

[Snidely Whiplash]

Originally Posted by shank0668

Could have potential for a track car.

Originally Posted by Camaroshark

Could have potential for street cars.

Could have potential for a FUN car.