Wiki says you are at 1565 ft above sealevel.
You never said what size Magnum you have but no matter, if 1565 is correct, you are gonna need a lot more than 9/1 Scr to get any power at all.
Torque will be OK but nothing to get overly excited about.
As it stands he either has to get compression way up, or choose another cam. 1500 ft above sea level isn't that much though. I am at 1000 here in Atlanta, and with a little over 9.1 that cam makes 165psi and runs good in my van- or at least it did when it was a fresh build 30k ago.