When do you get full boost? Does it come on at only 3k RPM? In sport, I get the overboost arrow and the car is like a rocket. I've seen maybe 15 lbs on the number gauge, but never 18 lbs. Possible the I've never gotten into the insane speeds to get the full boost. Also, even with the overboost arrow on, the boost will fluctuate if I'm not on full throttle. Judging from the performance, I don't think there are any issues. I will say that with my GTR, I definitely had full boost at moderate RPMs. Just wondering if the TT motor needs higher RPMs before it is giving full pressure.

This does not address your question but may serve as a data point for someone else:

2012 997 Turbo S
Europipe and Sportec tune
Max boost pegs 18 PSI

Walt

WaltB, Your car actually SAYS 18 PSI? I have the exact same car as you, with GMG Exhaust, And I've NEVER seen 18, only 17 MAX and only at certain RPM's.

I'm not sure I understand... When I run my car in non-Sport mode, I'm also able to see 17 PSI at certain RPM's, and they then drop to 13-14 PSI.

Same goes for Sport Plus, 17 PSI at certain RPM's, and then drop down to 13-14 and 15. Never seen past 17. Even if the car showed 17 and was doing 20, wouldn't that mean that instead of dropping down to 13-14, it would drop down to 16-17? I honestly didn't see any change boost-wise with the tune. I did see performance difference, tune was great, just no boost difference. I would like to talk to you about it though, if you'd like to PM me a number I could call you at on Monday?

Thank you.

Yes I see 18 PSI and then it slowly drops off as I accelerate.

Maybe the higher altitude/thinner air in Bogota is the reason you are seeing less? Or could be the tune. The tune by design increases the boost for more power I believe.
The Turbo S sport button has no affect on boost like it does on the sport chrono Turbo.

I'd be glad to video for you when I get back in the US.

Walt

WaltB, if it would be too much to ask could you take a pic or a small video of your boost? I've actually made a few videos of my car during boost and it never goes past 17.

On this video;
You can see the boost go up to 17 as well, but never past 17...

There are 2 boost gauges, one displays a single number up to a max of "17" and the other shows a horizontal bar range from 0-18

Walt do you see "18" displayed in the single number display (which shouldn't display more than 17 IIRC) or you see the bar extend out and touch the far right of the second gauge which has an 18?

I've had questions about this as well. A friend and I compared our cars and there was a difference in boost showing even with same modifications and APR tune. He has a 997.1 2009 and reads 17 with arrow, I have a 997.1 2007 I have never seen anything over 15. ?????????

I have a 2007 997.1TT and when I have the psi gauge readout showing the actual numbers I see 17psi in overboost / sport all the time.

Would there be any reason I would not be seeing the same as you?

How do they run together if you dont mind?

Okay so first the actual mod lists.

2009 997 turbo- fabspeed 70mm catless mufflerless xpipe, gt2rs Intercoolers, forge DVs, APR tune on 93 octane.

2007 997 turbo- FVD sound brombacher 200 cell, fabspeed headers, IPD 74mm plenum and larger ypipe, APR tune on 100 Octane. Stock intercooler, stock DV.

We ran a few times. 09 always hitting 17psi, mine 15psi on the stock gauges. Again he was on 93 and im running the 100 octane program. We started at low rpm in 2nd gear, forgive me for not remembering. Every time I would gain just a bit past his front bumper right from the start, after 3rd there was no movement all the way through 4th.

This boggles my mind about the boost difference. APR assures me we are pulling the same psi however the boost gauges are showing otherwise. I have sport Chrono just as he does. With both have sport on and psm off.

And I figure I would be more out in front on the race. I'm thinking that his straight pipes and DVs have a big advantage over my muffler 200 cell system and stock DVs....

As stated, to see the 17 Lb of boost on the gauge you must have the sport chrono package. Also, regardless of what boost you run, the stock gauge will not show more than 14 or 17. If you go over that, it does show an up arrow all the way on the right of the boost bar.

512bb, this also happens on the Turbo S? I'm wondering if I would see an arrow if I go above 17 PSI?

2007 997.1 TT w/Sport Chrono, 46K miles, stock motor/ECU.

93 octane from a random gas station, 65F, 44% humidity, sea level.

My bar graph reads to 18PSI.

WOT in 5th gear at 70mph with sport mode on - triggers overboost and yields 17PSI in both the digits-only and the bar graph.

Without overboost I think I usually just see up to 14 PSI.

I haven't eyeballed the RPM gauge yet but boost drops off a little as I'm in the upper end of the rev range.

I tried doing pulls in 3rd and 4th but it was more difficult to max the boost.

Somewhere along the line your dealer or someone else had to do some ECU work on your car and did not flash it correctly.

Happened to me once after getting my car back after taking it to the dealer for the P0021 cam flaw (major work to fix). Went back and they corrected in a few minutes with the PIWIS tool.