Yes a trubo would be good to have on this.
No the comp. ratio would figured : P/Po=(CR)^k pressure ratio of an Isentropic expansion which a desiel cycle use.
Then your final P=Po*(CR)^k where Po is your init. pressure, CR=compression ratio, and k =cp/cv=specific heat ratio= 1.4 (using air b/c the charge is still comprise mostly of air)
Keep in mind that P and Po are expressed in either in psig or Mpa. But stick to either metric or english/SAE do not mix. Both k and CR have no units think about.
If we allow initial Po=14.7psig and P=to solve for, k=1.4, CR=22.7:1 or just 22.7 plug these all in and solve for P. P=1163.5psig final (cylinder pressure).
Now enter your Po=15 psi boost =29.7 psig would make P=2350.7psig final
That would be like running a CR ~37.55:1 :yes:
Hope that helps.
BTW I think that motor can handle as long as you keep fuel supply in mind.