Pontiac Solstice Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
432 Posts
Discussion Starter #1
So I have owned my GXP with GMPP tune for two years now and I have always only ever topped out at about 19psi occasionally blipping to 20psi for a second but that was it. Now suddenly I am starting to see 23psi blipping to 24psi on occasion but more frequently 21psi blipping to 22psi. Nothing has been changed on the car recently so why did this suddenly start happening and is it ok/safe? I know in general I want more boost but a sudden surge of 4-5psi makes me concerned.
 

·
Registered
Joined
·
7,260 Posts
Boost pressure depends on a host of things, gear, revs, outside temperature, humidity, and elevation. One or more of these things may have changed for you (or you are just now looking at the right time :)). I can regularly touch 24PSI in 4th gear, pedal to the metal.

Nothing to worry about.
 

·
Registered
Joined
·
432 Posts
Discussion Starter #3
Boost pressure depends on a host of things, gear, revs, outside temperature, humidity, and elevation. One or more of these things may have changed for you (or you are just now looking at the right time :)). I can regularly touch 24PSI in 4th gear, pedal to the metal.
Nothing to worry about.
In my situation the only one of those that could have changed is humidity (because that is the one variable I cant control obviously) It just worried me as in two years it never did that before and now suddenly it does.
 

·
Registered
Joined
·
245 Posts
I just got a gmpp tune installed and saw it hold 21psi and flash 22 and 23:thumbs: I am very happy with my tune. I don't know why yours hasn't produced this much boost until recently, but it sounds normal. I say enjoy!:yesnod:
 

·
Registered
Joined
·
346 Posts
I have hit 24 psi also without an issue (TrifectTune) and I believe it has to do with elevation in my area.Happy with my tune also.
 

·
Registered
Joined
·
551 Posts
GMPP here and can get 20-21 steady and peaks of 23-24. As TS said, a lot of things affect the way these cars run. I only get the 24 psi peaks when it's sunny and in the 80's. If it's cloudy and cool, I'll only see 20-21psi.
 

·
Registered
Joined
·
257 Posts
When monitoring boost pressure are you guys using aftermarket gauges or do later model years read higher levels in the DIC? My '07 will only read to 23psi. MY car is tuned and has seen much higher boost levels, but still displays 23psi max.

For me on GMPP I would see 18-19 when it was pretty cool out like 45 or less. Boost creeps up to 21-22(occasionally 23psi) when its ~70+.
 

·
Premium Member
Joined
·
10,474 Posts
I do not believe the DIC shows any higher than 23psi.
 

·
Registered
Joined
·
1,639 Posts
My 2008 with GMPP tune will display well above 23 PSI. I tend to see peak boost of 26-27 PSI in the summer
(I am at 5000 feet above sea level, so 26-27 is equivalent to 23 at sea level).
 

·
Registered
Joined
·
278 Posts
Wasn't there something about 2 or 3 bar MAP's? 2 Bar can only handle readings up to 23psi? Isn't stock a 2 bar, the GMPP upgrade are 3 bar?
 

·
Premium Member
Joined
·
10,474 Posts
The original sensors are 2.7 Bar and the GMPP are 3 Bar.
If that is the case on a 2008 I wonder if that was one of the upgrades to the 2008 and later ECM's
The other answer could be in the tune parameters from the GMPP tune.
I know my 2007 does not display above 23psi and I know with my upgraded turbo larger wheel and tune it goes higher than 23psi.
 

·
Registered
Joined
·
1,639 Posts
If memory serves:

All stock Kappas have the 2.7 Bar sensors. Only the GMPP tuned cars got the 3 Bar sensors.

The 2007 model year would not display above 23 PSI.

2008 and newer would display above 23 PSI, even with just the 2.7 Bar sensors; those with aftermarket tunes can see the higher boost, even on the stock sensors.

It seems to me that there was a programming change in the base flash, from what I remember. But someone else will have to verify.
 
1 - 14 of 14 Posts
Top