I really don't think 1/2" head studs are neccessary over the standard size ARP head studs. An improvement, yes, but not necessary. Also, the radiator isn't the problem because I'm using an aluminum Fluidyne radiator with dual FAL 2100 CFM fans. Flow through & around the intercooler is fine.

Currently, I'm using ARP head studs torqued to 100 ft.lbs. and a 4-layer MLS teflon-lined headgasket. It's had a couple of years worth of high boost with nitrous runs on it. Recently, during some MegaSquirt testing, I overheated the motor to 270+ degrees at idle and blew the radiator cap off the t-stat housing (don't ask how I let this happen). The motor has been running super strong since then, but I can't help thinking that it was the start of my current issue. I'm seriously thinking headgasket here.

If I do have to pull the head off, then 1/2" studs will go in along with o-rings and an all out race-prepped head in preparation for new GT35/40R turbo setup.