you can use the stock cam for a low boost turbo (less than 15 psi). The amount of overlap the turbo can handle depends greatly on the turbine selection. A low rpm boost turbine can't handle any overlap.
set compression at 8:1 for 8 psi of boost.
In theory, a 245hp/330 ftlb tpi 350 with 7.5 psi of boost should make 50% more power (368hp/495ftlbs).
8 psi should make 378hp/510 ftlbs
10 psi should make 412hp/554 ftlbs
12 psi should make 445hp/597 ftlbs
15 psi should make 490hp/660 ftlbs
yes, the tpi intake is restrictive, but boost will change that. However, better to use a regular intake design that is modified to hold injectors.
if you plan to run more than 10 psi of boost then use 7.5:1 cr.
proper compressor and turbine selection is critical.
A couple of first generation 300zx turbos (T3, 1984 to 89) would work well to 12 psi of boost on a 350. Use a good bar and plate intercooler.