Has anyone thought of purchasing the 997 GT2 Intake Distributer for there 997 Turbo. Parts are about one thousand dollars.

-Pauly

 

Dont think you can bolt on and drive, I would think it needs some ecu tweaking to take advantage off? Not sure.

 

GT2 intake subtracts/eliminates .2 bar from the boost pressure. Putting it on a stock TT will mean you will drop to 0.8 bar (or 1.0 bar on Sport mode). You will lose power unless you use the bigger Gt2 turbos or get special ECU programming to increase boost pressure from the stock VTG turbos.

 

Really? Why would Porsche put on a system that actually subtracts boost pressure? Is it so that the GT2 turbos don't overwhelm the system?

 

The intake is designed to cool the air almost like a secondary intercooler thru gas expansion. With any expansion the boost pressure decreases. The GT2 turbos are setup to produce 1.4 bar pressure, unlike the std TT turbos.

 

That would make sense. Thanks for explaining that. I was aware that the GT2 produced 1.4 bar pressure but had no idea that the GT2 intakes were that restrictive.

 

not restrictive, rather expansive! The GT2 intake is like a poster tube vs a drinking straw - blowing into the poster tube doesn't generate near the pressure as blowing into a drinking straw

 

Okay, good analogy, I get it now. It'd take a much greater amount of effort to blow through a poster tube than a drinking straw. I get why the GT2 intakes wouldn't work as well for a TT now.

 

i think that loosing 0.2 bar doesn't necessarily mean loosing hp. the gt2 intake is less restrictive, you should get the same air volume but with less resistance (back pressure). this back pressure is the boost number we see on the gauge. we could actually see less boost and more hp.

 

I thought the GT2 used the same turbos on the TT

 

You are confusing a few things here. Back pressure is the pressure on the exhaust side and is not what is read on the boost gauge. The boost gauge reads the pressure on the intake side - the filling pressure of the combustion chamber. The volume of the combustion chamber does not change - it is fixed. You are still filling a 3.6l volume engine with air. The theoretical advantage of the GT2 intake is to decrease the temperature of the intake air to hopefully produce more power and cause less knock, less detonation, and allow more ignition timing. Both the TT and GT2 have the same 1.2bar of pressure filling the combustion chambers but the Gt2 makes more power. Porsche claims it is from the intake, I think it is simply from maintaining 1.2 bar to redline instead of it dropping off like in the TT. Notice the Gt2 does not make any more torque than the TT, which is a clue that the intake system in reality is not achieving much gains at all.

 

No, the GT2 most definitely does NOT use the same turbine units as the TT.

 

i didn't mean back pressure as in exhaust back pressure. what i meant is the amount of air being restricted from going into the engine easily. so this air volume gets "backed up" until the intake valve opens and then it goes in.
i appreciate your explanation , and i would be greatful if you would tell me if my reply/understanding of this boost theory is wrong ?

 

gas expands with heat and a hotter gas in a fixed volume creates more pressure. Just like a hot tire has higher pressure than a cold tire - no air has been added at all. Porsche thinks that if they cool the intake air with the GT2 manifold the air will be more dense and create more power than a hotter air. Problem is the GT2 turbo running at 1.4 bar probably heats the air up higher than the TT turbo running at 1.2 bar. I think the Gt2 intake only cancels out the hotter air produced by the Gt2 turbo, so it may be alot of engineering for nothing.