ATS recommends the use of a head stud kit with the use of their Aurora 5000 or the Compound turbo setup. The boost pressures produced by these setups can reach 70 psi! Don't take a chance with stock when you're running this much boost.

Here's what ATS has to say about their head stud kit:

Head Studs are a must for any Cummins engine producing turbo boost pressures above 50 PSI. ATS offers Head Studs in two different sizes. For moderate performance and towing applications, dropping in 12mm Head Studs is adequate. When looking for extreme performance and absolute reliability, the extra large 14mm Head Stud Kit is the answer. When installing 14mm Head Studs, the head must be enlarged for stud clearance and the block must be drilled and tapped. This is an excellent choice when rebuilding a Cummins engine.