Your low boost number is probably due to the weak stock wastegate actuator. With your hotter programming, the PCM isn't instructing the wastegate to open yet at only 23 psi (I'm assuming /ubbthreads/images/graemlins/smirk.gif) but the weak stock actuator can't keep the wastegate shut, regardless.
I installed the Banks Big Head actuator on my truck this weekend (along with ATS housing and ITP boost regulator, too). Previously the highest boost I'd seen was 21 psi. First time getting on the freeway, I stepped on it and boost went up to about 28 psi. /ubbthreads/images/graemlins/smokin.gif This is with the SCMT on I'm not sure what level. Anyway, with the Big Head, it's strong enough to hold the wastegate shut until it's told to open by the PCM... it's adjustable, as well. I'd recommend it. A bit pricey, but seems to do a great job so far. /ubbthreads/images/graemlins/cool.gif
Just thought I'd recommend it based on my recent experience.
edit - I should also mention to check for any boost leaks, too, which could be costing you boost.
I installed the Banks Big Head actuator on my truck this weekend (along with ATS housing and ITP boost regulator, too). Previously the highest boost I'd seen was 21 psi. First time getting on the freeway, I stepped on it and boost went up to about 28 psi. /ubbthreads/images/graemlins/smokin.gif This is with the SCMT on I'm not sure what level. Anyway, with the Big Head, it's strong enough to hold the wastegate shut until it's told to open by the PCM... it's adjustable, as well. I'd recommend it. A bit pricey, but seems to do a great job so far. /ubbthreads/images/graemlins/cool.gif
Just thought I'd recommend it based on my recent experience.
edit - I should also mention to check for any boost leaks, too, which could be costing you boost.