There aren't many differences between them, one being the new forged pistons and aggressive tuning to get the upped power. other than that I do not know.

Hey, no problem mate!I know that keyboards are not the best way to express our feelings...Attachment 128107

Until we get inside a GTRS, or hear directly from someone at Porsche...we will continue to guess on what it has internally, but I'm pretty sure it's the same as a standard 997 motor.

Regardless, consider the following:

-The 996 and 997 use exact the same rods, pistons and block (all of which are ridiculously strong from the factory)
-The 997 breathes better due to some headwork and different cams
-The 997 has a better fuel system
-Switzer has a car running 915 whp on stock internals (app. 1045 crank HP)
-Protomotive has two 997 GT2s and one 997TT (that I'm aware of) making in the 850 rwhp range (970 crank HP)

Considering all of that; making a reliable 620 crank HP (which is only around 545rwhp) on standard 996 or 997 internals seems like it would be a pretty easy task.

1.6 BAR?! Ha ha...no wonder it makes so much power with those little turbos.hilarious

Kudos to Porsche for making the best car on planet earth (IMO)!

Scott when refer to 996 and 997 you are talking about tt's not GT2 996 and GT2 997 right ??

Yep, and all you need to get a warranty with that power is $245,000.

Both.

996TTs, 997TTs, 996 GT2s and 997 GT2s all use the exact same rods, pistons and block.

Thank you Scott that make me happy,i have a good car:)

I think its interesting Porsche was clapping hands about the A91 series and how they were able to up throttle response by running a higher CR with DI and less boost. But then its right back to the Metzger motor the second they need to make big reliable power.

Don't be so sure that the A91 isn't going to be in the 997.2 GT2.

I think it will be, I thought they would use it in the 997.2 GT2 RS since they said it was the future.

According to this, the rods, pistons and block are the same as what's in any other 996 or 997 Turbo or GT2:

Looks like all they did was use different ICs, intake manifold, increased boost and a tune:

Engine and powertrain
The high-performance engine of the new 911 GT2 RS is based on the bi-turbo engine of the 911 GT2 and thus features the following highlights:

• Flat-six bi-turbo engine, with 3.6 l displacement and intake manifold injection
• 2 turbochargers with variable turbine geometry (VTG)
• Camshaft control and valve lift adjustment with VarioCam Plus
• Expansion intake manifold
• Dry-sump lubrication with external engine oil tank
• Forged pistons and connecting rods
• Rear silencer and tailpipes made from Titanium

For the new 911 GT2 RS, the engine has the following features:

• New plastic expansion intake manifold
• New charge-air coolers with markedly improved efficiency
• Increase of maximum boost pressure
• Adaptation of engine control, including injection system and ignition
• Single-mass flywheel (911 GT2: dual-mass flywheel)

With these modifications, the new 911 GT2 RS gives the following improvements compared to the 911 GT2:
• Power output increased by 90 hp to max. 620 hp
• Torque increased by 20 Nm to max. 700 Nm
• Power output per litre increased by approx. 17% to max. 172.2 hp/l
• Weight-to-power ratio improved by nearly 20% to 2.21 kg/hp

Scott,

Not exactly so.

Up until 2009 what you are saying is so. In 2010, the 997tt does not have the same or even close to the same parts. The 2010 GT3 and 997 GT2 RS does have many of the same parts as the 996tt, 996GT2 and 2009 and earlier 997tt Aand 997 GT2's.

Scott, doesn't 1.6 bar sound like a lot more than 620 crank hp?

Are you talking about the 3.8 DFI in the 997.2?? :D

Because I'm pretty sure that everyone other than you clearly understood that I was talking about the 3.6L Metzger that's in the 996 and 997.1 cars.