May be a stupid question
 

When talking about boost for a motor, is the boost number the amount of pressure above normal atmosphere? i.e. 10 psi = 10 psi or 10psi = 10+14.7=24.7psi?

Boost is above normal atmosphere.

its shown in psig, which doesnt include atmospheric pressure..

otherwise that would be absolute pressure

Ok cool thanks for the quick replies