So John are you saying that suddenly this is a change from the norm in your GXP or that the way the GXP is 100% new to you and you're unsure if it is the way it's supposed to work?
15 psi is fairly representative of the norm in my experience, but your elevation can affect that...in Florida I'd say you're close to sea level. I live fairly close to the ocean and see 15psi as a normal thing, but the range has been 14-18psi depending (two different GXPs), before I installed the GM turbo upgrade tune in my previous GXP. Afterwards I'd see 18-22psi.
I grew up with big V8s as well. Mounds of torque is a sensation that is distinct. You have a really nice flat torque curve in your GXP, but it's not the same as a V8 with tons of low end torque. Turbo cars will experience lag to some extent. In my experience the manual trans Sol GXP has about as much turbo lag as a family sedan's auto trans downshift.
You have a variable vane turbo and a variable valvetrain and a blowoff valve in your GXP. But that won't completely negate turbo lag. Soon you will adjust to the way this car drives. I think you'll find the gear spilts (if manual trans, I never drove an Auto Solstice of any type so I can't comment there), the torque curve- which is damned near flat- and the final drive ratio are a really nice combo, but you will need to expect a touch of turbo lag.
Driving and working on a Sly 2008 Solstice GXP 5spd 260/260, and the worst-built 2012 LS3 Camaro 1SS to escape from Oshawa.
Gone but not forgotten:
2007 Solstice GXP 5 speed 290/340
Stored and needing to part ways with a 1970 Skylark Custom convertible I have owned since 1989 and turned into a GS455 clone. 462 with 7/8 primary headers, adjustable roller rockers, TA Performance Stage 1 aluminum heads, auto, Chevy 12 bolt, 3.31:1. Sadly a project car now but a driver from '89 to '06.
Last edited by ChrisBlair; 05-15-2019 at 02:52 PM.