It's a known issue that the ARP head studs do not bottom out in the SR20 block like they're supposed to, that's why the Mazworx kit exists. It has over twice the thread engagement with a bullnose tip to full engage all of the threads available.
This means that with less torque they actually have a higher effective clamping force.
http://www.mazworx.com/store/p/141-M...-stud-Kit.aspx