Hey guys!

My name is Ammein, a nearly new owner of a 2009 997 gt2 and a new joiner on rennlist. This is my second Porsche I own, first one was a 2007 manual 997 turbo, eventually tuned to 580bhp. After selling the turbo 2 years ago I couldn't live without a Porsche in my life. Then the chance arouse to a very clean, beautiful 2009 gt2 with the exact spec I would of ordered it if I was to purchase it from new, so obviously it was a no brainer to buy it.
It's on a TOTAL different level compared to the 997 turbo when it was tuned to 580bhp in all aspects, its a true Widowmaker and I absolutely love it.

Here is where I need your guys help. The car was pulling very hard considering it was stock. I was getting 1.4 bar from 2nd gear through to 5th gear; around 5500-6000 up to 6500 rpm (I wouldn't get to extreme high speed on 5th and would back off myself ) However its been a week now that instead of 1.4 I'm only getting 1.3 bar from 2nd and I only start getting 1.4 at 5th gear, (same rpm as before expect it'd start at 5th gear only)

I took it to the local Porsche dealer and they checked intercooler pipes, they carried out a pressure test for all pipes, checked o2 sensors but all were okay.
I started reading more on forums and found that there has been similar problems in cars like mine but I could not find an answer as to how it was solved and got back to normal.

(PS the car is in same weather conditions and same fuel- 98 oct)

 

Because of the way the Motronic works ie it tries to hit preprogrammed torque targets the boost can vary throughout the rev and load range depending on many factors including climate conditions and loading and gear.

So you may in fact be getting the correct performance and power but with slightly less boost. You typically get less boost in colder conditions and more in hotter.

The best way to test all is well is do an acceleration run 100-200kph and see if it matches factory performance which is 7 to 8s, if its taking a lot more then you have a problem (presuming your gear shifting is reasonably proficient )

 

^ This. The air is extraordinarily cool for us in the desert around this time of the year. I'd wait until end March before doing more digging, your Turbos should be hard at work again.

 

^^ Agreed. Temps and density make a big difference. In Houston, TX I go from hot and very humid in Summer to days like today where its dry and in the low 40's F. Gotta be close to a 50+ lb ft swing between those two conditions - and we are blessed with good 93 octane pump gas and sea level here. I'd give it some time and make note of air conditions with each test.

 

By the way, big congratulations! You own one of the best, most thrilling production cars Porsche ever made.

 

TB993tt thanks for the simple yet detailed information. I'm going to go for a few runs tonight and update you all with the results I'll be getting.
I heard that temperature could affect this factor (simple but short; lower temperature = better performance compared to higher temperatures such as 30-40 degrees Celsius). I hope this is the case because right now the temperature here in the United Arab Emirates varies between 18-22 degrees Celsius at night, however I was still hitting 1.4 bar in these conditions, and thats why I'm a little confused weather it is indeed the lower temperatures we are experiencing or weather its something mechanical or the ECU has pulled the car back...

Thanks again guys, I'll update you all with the results I'll be getting !! I'm hoping to hit that predicted 7.7 secs

 

Reid55 thanks my man!! I totally agree with you, the GT2 is a complete beast and in my eyes I would not own another Porsche (wouldn't mind a GT2 RS though)

 

FWIW: I have an '09 and the maximum boost indicated in the digital display is 21psi.

 

So guys, I have the results..

Temperature was varying between 19.5 - 21 degrees Celsius. I had between 1/4 - above the red line in the tank filled with 98 RON fuel.

I done around 10 runs and I got the same results over and over again. Ofcourse they aren't 100% accurate as I was recording from the chromo and on other occasions from the IPhone Stopwatch to take a average/ make sure I was doing it correct and compare the results. (I was making note of the speed from the speed cluster and not the digital as I found it more accurate to record the speeds compared to the digital as it jumps high numbers under full throttle as I'm sure all you folks know)

Getting back to the point, I was getting between 7 - 7.2 secs over and over again…

When I was recording the time from the iPhone stopwatch i had the display put back on bar display to show me the boost reading. In 3rd gear it was 1.3 bar. As I let off the accelerator to change to 4th I would see 1.4 bar, and then on 4th gear in some runs I was seeing 1.4 bar around 5500-6000 rpm.

Let me know what you guys think of the results, if anything is it pulling hard considering its stock??

 

Does not sound like any problems with boost. On a side note, best performance requires cool air flowing through those IC's. If you are doing hard pulls then stopping, idling and setting up for the next run, the ECU is likely dialing the car back a bit. Keep her breathing.

 

Thats exactly what I was doing. Didn't stop in-between runs, just slowed down a bit, low rpms moving through nice cool air.


I now know at this point that theres most likely no problem however I'm thinking of either the EVOMS boost recirculation valve or the agency diverter valves as a replacement to the OEM.
What do you guys think? Is it worth it or not??

 

Your 100-200 times indicate that there are no power issues.

 

post pics of the gt2

 

Same thing happens on my GT2, it could be weather dependant or the fact that you're getting used to the power.

Congrats on an absolute beast of a car!

 

I figured out it was just the weather, and maybe some bad fuel! I don't think I can get used to the power Its the way it puts the power down… Absolutely brutal but I love it

Thanks my man, I think were all lucky to own such beasts