I'll give that a try, thanks for the suggestion. I did not want to bug the HPT folks with questions until I learn more about how the software works. I did get some interesting results on the way home with warmer air temps. BIG difference in first gear. At 35 deg F this morning I was reading 7 psi in first gear (coolant at 192 F) consistent for 2 runs. On the way home air temp was 74 to 77 deg F (coolant at 194 deg F) and I read 12 psi in first gear, 4 runs, with way more wheelspin and an obvious increase in Torque. I'll be interested to try the low temp again next week. Altitude (SL to 1900 ft) did not seem to make a difference. It seems that the boost is compensating for air temp (and resulting air density) but the difference in power is so obvious that the reduction in boost at lower temp seems excessive.

 

I am getting similar numbers with my HP Tuners and the boost gauge which
is not a pressure gauge but is a digital gauge being driven off map sensor.
I have both a Solstice GXP and HHR SS and I can tell a BIG difference
in boost and acceleration in 1st gear. The PCM is really playing alot of
tricks in the HHR vs the GXP, especially in 1st gear. Wester Garage, a
long time GM program guru, has broken more of the code than HPT so far
and has a tune for GXP's that holds a steady 22-23 # in all gears without
the pcm messing with boost while maintaining esc control and ETC control.
Do not think you could use that much in 1st gear and have any kind of traction.

turbofreak

 

I reallyl havent seen any thing high than 15psi... but it has been cold.. really waiting to see some higher numbers

 

You guys are lucky, on the Canadian model the changed the gauge to kpa, so i see around 60-70 in first, 90-100Kpa in the other gears. Why couldn't they just leave it in psi!

 

On the test drive I know I hit at least 15 PSI

 

Just one more data point today 64 deg F ambient temp, engine fully warmed up and coolant at 194 deg F, 3rd gear, 15 psi to 4500 rpm, then increasing to 18 psi at 6000 rpm (pulling very strong). I think it takes 80 deg F + to hit 19 or 20 psi, but it probably is monitoring temperature at the outlet of the intercooler anyway.

 

Well I had my Victory Red for 2 weeks now and it has an Auto Slushbox.
I have seen spikes of 12PSI but usually seing around 10 PSI in 1st and 2nd.
It comes out of the whole nice but 2nd seems long and dull. The car feels great overall though I am really happy if my wife could drive a 5-Spd I would have gotten one.