No doubt, but I'm not talking about 10 minutes of warm up. Like only when the oil is at full operating temp.

 

I finally got out today and was able to confirm my results were identical to djben's.

2008 997.1 TT cab w/Sport Chrono, 16K miles, stock motor/ECU.
91 octane from a random gas station, 68F, 25% humidity, sea level.

A couple of additional observations:
1) Bar graph was the same, 0-9-18 in both sport and normal modes. My thought on the variance others are seeing is that it is similar to an excel graph; scale will adjust to the fit the max data inputs from ecu. We know this ecu has multiple OEM program settings for cars with and without sport chrono, thus the different max data values and bar graphs. It would be interesting to see if the bar graph adjusts higher for someone who has programmed their overboost greater than 18.
2) I did most of my 70-90 pulls in 6th gear to give me time to watch the gauge. However, I did one sport mode pull in 5th and noticed the boost started bleeding off at 4000 rpm before the 10 seconds overboost period was up. I also did a 3rd gear pull and never saw the guage hit max boost of 17 before having to shift which makes sense if ecu is programmed to start tapering boost at 4000 rpm; the engine is simply reving up to quick to get an accurate max reading on the gauge in the lower gears.

That's my .02 on this. Great post guys!

 

I'm the OP. Today I took out the car from storage and yes, the gauge goes from 0-14 psi only. So as soon as the snow is gone, off it goes to the dealer to fix the programming.
I'm pretty sure I'm not getting any over boost. It would be interesting to know what the gauge reads on a Turbo without sport chromo. Does such a beast exist?

 

Yes, I don't have SC--gauge pegs at 14 as someone previously stated but could never hit that with stock programming. Mine only hit 14 after I flashed it.

 

Very interesting thread! Now my question is:

If I wanted to install an aftermarket boost gauge, where is the best place to tap the boost vaccum line? Is there any vaccum source available directly on the manifold?

 

My '08 does not have SC. It does have the Champion '700 package' with the GIAC tune. Gauge reads psi-7-14. Most boost I've seen on the digital reading is 15. I asked about this at their open house-before this thread got started-they concluded I should bring it in to have it checked out.........I'll do that soon.

 

So i took the car to the dealer today; no leak with pressure test. Dealer says normal to hit only 14 psi in sport mode. Something else to look at or is this accurate?

 

The answer is really simple.

If your ECU is stock and you follow the above procedures for maxing boost then your dealer is wrong.

 

Find a straight stretch of road, select Sport and mash the pedal in 3rd or 4th and you should see over boost.

 

Yes, I have tried in 3rd, 4th and 5th. 2-4k rpms; Cannot get above 14 in sport mode. Never saw an up arrow
Do i have them update the ECU? I also read lubing the turbo linkage can help - i dont know how to direct my conversation with the dealer

Stock ECU as well, no mods

 

Your conversation with the dealer is pretty simple - just tell them that overboost function of Sport Chrono isn't working. That's very easy to test on a test drive...in fact you already have.

 

Would this be an ECU issue or something mechanical? Wanting to help direct my conversation with the dealer before going elsewhere for another opinion.

 

Just another 2010 data point... my unmodified 2010 with SC also shows 0-7-14 all the time (doesn't change with sport button). I see the up arrow on overboost but scale never changes.

 

Same here, '07 TT 20K miles scale shows 0-7-14 which doesn't change with sport button but I do see an UP arrow with the over boost...

However I did have an ECU issue which the dealer swapped out for another one.

I just talked to the service manager and he thinks this is normal for the car and that they did re-calibrate the new ECU when it was put in.

 

Apologies for adding to the noise. I spent a few min with google and it looks like 997.2 cars have max boost set at 11.6 psi (.8 bar) and with overboost you get back to 14.5 psi so it makes sense that stock 997.2 cars should always have 0-14 scale. I confirmed on the way home today (did a couple of 6th gear 70 mph pulls) that with overboost arrow I hit 14 psi consistently (but only for about 2 seconds before the revs climb and boost drops).