Fair enough. Pete from v1r ran 24 psi and saw coolant issues on his 700+qr he holds the fastest 1/4qr in a b13 in the 9s i think he would know what psi is safe with which arp stud. Mind you this is strictly track car 8500rpm at 160mph in 4th gearYour correct about flow, but on the EXHAUST side. PSI is PSI. Your CFM of the turbo determines what you can push into the engine, yes, and how efficient you can maintain a pressure. But pressure is pressure. 28 psi is 28 psi is 28 psi weather the turbo is off a fork lift, a semi, or a sentra. The difference is how much heat and flow is behind that pressure, which is where power comes from with a larger compressor wheel. Less heat, more flow. So in regard to the intake manifold, cfm wont kill the manifold, it is just pressure. The added heat of a smaller turbo obviously does not help.
Say your blowing through a straw into a pressure gauge with a balloon on the end. your trying to pop the balloon. With a small straw, you have to push the air a lot harder to build the pressure to pop the balloon. With a larger straw, you do not have to push as hard, and the balloon pops sooner. It took X PSI to pop the balloons in both cases, or really X volume, one way was just more efficient than the other.
As for the head stud thing; I ran 24 psi on my qr with normal arp studs without issue. On the jukes I run normal ARP studs well north of 28psi. Shit, the 400 whp 28psi juke I built was on OEM Nissan Head Bolts. Same diameter as the qr ones (i had not sorted out what studs from arp fit at the time and said fuck it)